mirror/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-01-17 12:32:27 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions
mariadb/sql/sql_partition.cc
unknown 46fc76534a Bug #17701, ALTER TABLE t1 ADD PARTITION for PARTITION BY LIST hangs test 
- code wrongly tries to do a "fast alter partition", although not supported


sql/handler.h:
  moved defines
sql/sql_partition.h:
  moved defines
2006-02-28 12:29:50 +01:00

5805 lines
190 KiB
C++
Raw Blame History

/* Copyright (C) 2005 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
This file is a container for general functionality related
to partitioning introduced in MySQL version 5.1. It contains functionality
used by all handlers that support partitioning, such as
the partitioning handler itself and the NDB handler.
The first version was written by Mikael Ronstrom.
This version supports RANGE partitioning, LIST partitioning, HASH
partitioning and composite partitioning (hereafter called subpartitioning)
where each RANGE/LIST partitioning is HASH partitioned. The hash function
can either be supplied by the user or by only a list of fields (also
called KEY partitioning), where the MySQL server will use an internal
hash function.
There are quite a few defaults that can be used as well.
*/
/* Some general useful functions */
#include "mysql_priv.h"
#include <errno.h>
#include <m_ctype.h>
#include "md5.h"
#ifdef WITH_PARTITION_STORAGE_ENGINE
#include "ha_partition.h"
/*
Partition related functions declarations and some static constants;
*/
const LEX_STRING partition_keywords[]=
{
{ (char *) STRING_WITH_LEN("HASH") },
{ (char *) STRING_WITH_LEN("RANGE") },
{ (char *) STRING_WITH_LEN("LIST") },
{ (char *) STRING_WITH_LEN("KEY") },
{ (char *) STRING_WITH_LEN("MAXVALUE") },
{ (char *) STRING_WITH_LEN("LINEAR ") }
};
static const char *part_str= "PARTITION";
static const char *sub_str= "SUB";
static const char *by_str= "BY";
static const char *space_str= " ";
static const char *equal_str= "=";
static const char *end_paren_str= ")";
static const char *begin_paren_str= "(";
static const char *comma_str= ",";
static char buff[22];
int get_partition_id_list(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_range(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_hash_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_key_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_linear_hash_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_linear_key_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_range_sub_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_range_sub_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_range_sub_linear_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_range_sub_linear_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_list_sub_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_list_sub_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_list_sub_linear_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
int get_partition_id_list_sub_linear_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value);
uint32 get_partition_id_hash_sub(partition_info *part_info);
uint32 get_partition_id_key_sub(partition_info *part_info);
uint32 get_partition_id_linear_hash_sub(partition_info *part_info);
uint32 get_partition_id_linear_key_sub(partition_info *part_info);
#endif
static uint32 get_next_partition_via_walking(PARTITION_ITERATOR*);
static uint32 get_next_subpartition_via_walking(PARTITION_ITERATOR*);
uint32 get_next_partition_id_range(PARTITION_ITERATOR* part_iter);
uint32 get_next_partition_id_list(PARTITION_ITERATOR* part_iter);
int get_part_iter_for_interval_via_mapping(partition_info *part_info,
bool is_subpart,
char *min_value, char *max_value,
uint flags,
PARTITION_ITERATOR *part_iter);
int get_part_iter_for_interval_via_walking(partition_info *part_info,
bool is_subpart,
char *min_value, char *max_value,
uint flags,
PARTITION_ITERATOR *part_iter);
static void set_up_range_analysis_info(partition_info *part_info);
/*
A routine used by the parser to decide whether we are specifying a full
partitioning or if only partitions to add or to split.
SYNOPSIS
is_partition_management()
lex Reference to the lex object
RETURN VALUE
TRUE Yes, it is part of a management partition command
FALSE No, not a management partition command
DESCRIPTION
This needs to be outside of WITH_PARTITION_STORAGE_ENGINE since it is
used from the sql parser that doesn't have any #ifdef's
*/
my_bool is_partition_management(LEX *lex)
{
return (lex->sql_command == SQLCOM_ALTER_TABLE &&
(lex->alter_info.flags == ALTER_ADD_PARTITION ||
lex->alter_info.flags == ALTER_REORGANIZE_PARTITION));
}
#ifdef WITH_PARTITION_STORAGE_ENGINE
/*
A support function to check if a name is in a list of strings
SYNOPSIS
is_name_in_list()
name String searched for
list_names A list of names searched in
RETURN VALUES
TRUE String found
FALSE String not found
*/
bool is_name_in_list(char *name,
List<char> list_names)
{
List_iterator<char> names_it(list_names);
uint no_names= list_names.elements;
uint i= 0;
do
{
char *list_name= names_it++;
if (!(my_strcasecmp(system_charset_info, name, list_name)))
return TRUE;
} while (++i < no_names);
return FALSE;
}
/*
Set-up defaults for partitions.
SYNOPSIS
partition_default_handling()
table Table object
table_name Table name to use when getting no_parts
db_name Database name to use when getting no_parts
part_info Partition info to set up
RETURN VALUES
TRUE Error
FALSE Success
*/
bool partition_default_handling(TABLE *table, partition_info *part_info,
const char *normalized_path)
{
DBUG_ENTER("partition_default_handling");
if (part_info->use_default_no_partitions)
{
if (table->file->get_no_parts(normalized_path, &part_info->no_parts))
{
DBUG_RETURN(TRUE);
}
}
else if (part_info->is_sub_partitioned() &&
part_info->use_default_no_subpartitions)
{
uint no_parts;
if (table->file->get_no_parts(normalized_path, &no_parts))
{
DBUG_RETURN(TRUE);
}
DBUG_ASSERT(part_info->no_parts > 0);
part_info->no_subparts= no_parts / part_info->no_parts;
DBUG_ASSERT((no_parts % part_info->no_parts) == 0);
}
part_info->set_up_defaults_for_partitioning(table->file,
(ulonglong)0, (uint)0);
DBUG_RETURN(FALSE);
}
/*
Check that the reorganized table will not have duplicate partitions.
SYNOPSIS
check_reorganise_list()
new_part_info New partition info
old_part_info Old partition info
list_part_names The list of partition names that will go away and can be reused in the
new table.
RETURN VALUES
TRUE Inacceptable name conflict detected.
FALSE New names are OK.
DESCRIPTION
Can handle that the 'new_part_info' and 'old_part_info' the same
in which case it checks that the list of names in the partitions
doesn't contain any duplicated names.
*/
bool check_reorganise_list(partition_info *new_part_info,
partition_info *old_part_info,
List<char> list_part_names)
{
uint new_count, old_count;
uint no_new_parts= new_part_info->partitions.elements;
uint no_old_parts= old_part_info->partitions.elements;
List_iterator<partition_element> new_parts_it(new_part_info->partitions);
bool same_part_info= (new_part_info == old_part_info);
DBUG_ENTER("check_reorganise_list");
new_count= 0;
do
{
List_iterator<partition_element> old_parts_it(old_part_info->partitions);
char *new_name= (new_parts_it++)->partition_name;
new_count++;
old_count= 0;
do
{
char *old_name= (old_parts_it++)->partition_name;
old_count++;
if (same_part_info && old_count == new_count)
break;
if (!(my_strcasecmp(system_charset_info, old_name, new_name)))
{
if (!is_name_in_list(old_name, list_part_names))
DBUG_RETURN(TRUE);
}
} while (old_count < no_old_parts);
} while (new_count < no_new_parts);
DBUG_RETURN(FALSE);
}
/*
A useful routine used by update_row for partition handlers to calculate
the partition ids of the old and the new record.
SYNOPSIS
get_part_for_update()
old_data Buffer of old record
new_data Buffer of new record
rec0 Reference to table->record[0]
part_info Reference to partition information
out:old_part_id The returned partition id of old record
out:new_part_id The returned partition id of new record
RETURN VALUE
0 Success
> 0 Error code
*/
int get_parts_for_update(const byte *old_data, byte *new_data,
const byte *rec0, partition_info *part_info,
uint32 *old_part_id, uint32 *new_part_id,
longlong *new_func_value)
{
Field **part_field_array= part_info->full_part_field_array;
int error;
longlong old_func_value;
DBUG_ENTER("get_parts_for_update");
DBUG_ASSERT(new_data == rec0);
set_field_ptr(part_field_array, old_data, rec0);
error= part_info->get_partition_id(part_info, old_part_id,
&old_func_value);
set_field_ptr(part_field_array, rec0, old_data);
if (unlikely(error)) // Should never happen
{
DBUG_ASSERT(0);
DBUG_RETURN(error);
}
#ifdef NOT_NEEDED
if (new_data == rec0)
#endif
{
if (unlikely(error= part_info->get_partition_id(part_info,
new_part_id,
new_func_value)))
{
DBUG_RETURN(error);
}
}
#ifdef NOT_NEEDED
else
{
/*
This branch should never execute but it is written anyways for
future use. It will be tested by ensuring that the above
condition is false in one test situation before pushing the code.
*/
set_field_ptr(part_field_array, new_data, rec0);
error= part_info->get_partition_id(part_info, new_part_id,
new_func_value);
set_field_ptr(part_field_array, rec0, new_data);
if (unlikely(error))
{
DBUG_RETURN(error);
}
}
#endif
DBUG_RETURN(0);
}
/*
A useful routine used by delete_row for partition handlers to calculate
the partition id.
SYNOPSIS
get_part_for_delete()
buf Buffer of old record
rec0 Reference to table->record[0]
part_info Reference to partition information
out:part_id The returned partition id to delete from
RETURN VALUE
0 Success
> 0 Error code
DESCRIPTION
Dependent on whether buf is not record[0] we need to prepare the
fields. Then we call the function pointer get_partition_id to
calculate the partition id.
*/
int get_part_for_delete(const byte *buf, const byte *rec0,
partition_info *part_info, uint32 *part_id)
{
int error;
longlong func_value;
DBUG_ENTER("get_part_for_delete");
if (likely(buf == rec0))
{
if (unlikely((error= part_info->get_partition_id(part_info, part_id,
&func_value))))
{
DBUG_RETURN(error);
}
DBUG_PRINT("info", ("Delete from partition %d", *part_id));
}
else
{
Field **part_field_array= part_info->full_part_field_array;
set_field_ptr(part_field_array, buf, rec0);
error= part_info->get_partition_id(part_info, part_id, &func_value);
set_field_ptr(part_field_array, rec0, buf);
if (unlikely(error))
{
DBUG_RETURN(error);
}
DBUG_PRINT("info", ("Delete from partition %d (path2)", *part_id));
}
DBUG_RETURN(0);
}
/*
This routine allocates an array for all range constants to achieve a fast
check what partition a certain value belongs to. At the same time it does
also check that the range constants are defined in increasing order and
that the expressions are constant integer expressions.
SYNOPSIS
check_range_constants()
part_info Partition info
RETURN VALUE
TRUE An error occurred during creation of range constants
FALSE Successful creation of range constant mapping
DESCRIPTION
This routine is called from check_partition_info to get a quick error
before we came too far into the CREATE TABLE process. It is also called
from fix_partition_func every time we open the .frm file. It is only
called for RANGE PARTITIONed tables.
*/
static bool check_range_constants(partition_info *part_info)
{
partition_element* part_def;
longlong current_largest_int= LONGLONG_MIN;
longlong part_range_value_int;
uint no_parts= part_info->no_parts;
uint i;
List_iterator<partition_element> it(part_info->partitions);
bool result= TRUE;
DBUG_ENTER("check_range_constants");
DBUG_PRINT("enter", ("INT_RESULT with %d parts", no_parts));
part_info->part_result_type= INT_RESULT;
part_info->range_int_array=
(longlong*)sql_alloc(no_parts * sizeof(longlong));
if (unlikely(part_info->range_int_array == NULL))
{
mem_alloc_error(no_parts * sizeof(longlong));
goto end;
}
i= 0;
do
{
part_def= it++;
if ((i != (no_parts - 1)) || !part_info->defined_max_value)
part_range_value_int= part_def->range_value;
else
part_range_value_int= LONGLONG_MAX;
if (likely(current_largest_int < part_range_value_int))
{
current_largest_int= part_range_value_int;
part_info->range_int_array[i]= part_range_value_int;
}
else
{
my_error(ER_RANGE_NOT_INCREASING_ERROR, MYF(0));
goto end;
}
} while (++i < no_parts);
result= FALSE;
end:
DBUG_RETURN(result);
}
/*
A support routine for check_list_constants used by qsort to sort the
constant list expressions.
SYNOPSIS
list_part_cmp()
a First list constant to compare with
b Second list constant to compare with
RETURN VALUE
+1 a > b
0 a == b
-1 a < b
*/
static int list_part_cmp(const void* a, const void* b)
{
longlong a1= ((LIST_PART_ENTRY*)a)->list_value;
longlong b1= ((LIST_PART_ENTRY*)b)->list_value;
if (a1 < b1)
return -1;
else if (a1 > b1)
return +1;
else
return 0;
}
/*
This routine allocates an array for all list constants to achieve a fast
check what partition a certain value belongs to. At the same time it does
also check that there are no duplicates among the list constants and that
that the list expressions are constant integer expressions.
SYNOPSIS
check_list_constants()
part_info Partition info
RETURN VALUE
TRUE An error occurred during creation of list constants
FALSE Successful creation of list constant mapping
DESCRIPTION
This routine is called from check_partition_info to get a quick error
before we came too far into the CREATE TABLE process. It is also called
from fix_partition_func every time we open the .frm file. It is only
called for LIST PARTITIONed tables.
*/
static bool check_list_constants(partition_info *part_info)
{
uint i, no_parts;
uint no_list_values= 0;
uint list_index= 0;
longlong *list_value;
bool not_first;
bool result= TRUE;
longlong curr_value, prev_value;
partition_element* part_def;
List_iterator<partition_element> list_func_it(part_info->partitions);
DBUG_ENTER("check_list_constants");
part_info->part_result_type= INT_RESULT;
/*
We begin by calculating the number of list values that have been
defined in the first step.
We use this number to allocate a properly sized array of structs
to keep the partition id and the value to use in that partition.
In the second traversal we assign them values in the struct array.
Finally we sort the array of structs in order of values to enable
a quick binary search for the proper value to discover the
partition id.
After sorting the array we check that there are no duplicates in the
list.
*/
no_parts= part_info->no_parts;
i= 0;
do
{
part_def= list_func_it++;
List_iterator<longlong> list_val_it1(part_def->list_val_list);
while (list_val_it1++)
no_list_values++;
} while (++i < no_parts);
list_func_it.rewind();
part_info->no_list_values= no_list_values;
part_info->list_array=
(LIST_PART_ENTRY*)sql_alloc(no_list_values*sizeof(LIST_PART_ENTRY));
if (unlikely(part_info->list_array == NULL))
{
mem_alloc_error(no_list_values * sizeof(LIST_PART_ENTRY));
goto end;
}
i= 0;
do
{
part_def= list_func_it++;
List_iterator<longlong> list_val_it2(part_def->list_val_list);
while ((list_value= list_val_it2++))
{
part_info->list_array[list_index].list_value= *list_value;
part_info->list_array[list_index++].partition_id= i;
}
} while (++i < no_parts);
qsort((void*)part_info->list_array, no_list_values,
sizeof(LIST_PART_ENTRY), &list_part_cmp);
not_first= FALSE;
i= prev_value= 0; //prev_value initialised to quiet compiler
do
{
curr_value= part_info->list_array[i].list_value;
if (likely(!not_first || prev_value != curr_value))
{
prev_value= curr_value;
not_first= TRUE;
}
else
{
my_error(ER_MULTIPLE_DEF_CONST_IN_LIST_PART_ERROR, MYF(0));
goto end;
}
} while (++i < no_list_values);
result= FALSE;
end:
DBUG_RETURN(result);
}
/*
Check that all partitions use the same storage engine.
This is currently a limitation in this version.
SYNOPSIS
check_engine_mix()
engine_array An array of engine identifiers
no_parts Total number of partitions
RETURN VALUE
TRUE Error, mixed engines
FALSE Ok, no mixed engines
DESCRIPTION
Current check verifies only that all handlers are the same.
Later this check will be more sophisticated.
*/
static bool check_engine_mix(handlerton **engine_array, uint no_parts)
{
uint i= 0;
bool result= FALSE;
DBUG_ENTER("check_engine_mix");
do
{
if (engine_array[i] != engine_array[0])
{
result= TRUE;
break;
}
} while (++i < no_parts);
DBUG_RETURN(result);
}
/*
This code is used early in the CREATE TABLE and ALTER TABLE process.
SYNOPSIS
check_partition_info()
part_info The reference to all partition information
file A reference to a handler of the table
max_rows Maximum number of rows stored in the table
engine_type Return value for used engine in partitions
RETURN VALUE
TRUE Error, something went wrong
FALSE Ok, full partition data structures are now generated
DESCRIPTION
We will check that the partition info requested is possible to set-up in
this version. This routine is an extension of the parser one could say.
If defaults were used we will generate default data structures for all
partitions.
*/
bool check_partition_info(partition_info *part_info,handlerton **eng_type,
handler *file, ulonglong max_rows)
{
handlerton **engine_array= NULL;
uint part_count= 0;
uint i, no_parts, tot_partitions;
bool result= TRUE;
char *same_name;
DBUG_ENTER("check_partition_info");
if (unlikely(part_info->is_sub_partitioned() &&
(!(part_info->part_type == RANGE_PARTITION ||
part_info->part_type == LIST_PARTITION))))
{
/* Only RANGE and LIST partitioning can be subpartitioned */
my_error(ER_SUBPARTITION_ERROR, MYF(0));
goto end;
}
if (unlikely(part_info->set_up_defaults_for_partitioning(file,
max_rows,
(uint)0)))
goto end;
tot_partitions= part_info->get_tot_partitions();
if (unlikely(tot_partitions > MAX_PARTITIONS))
{
my_error(ER_TOO_MANY_PARTITIONS_ERROR, MYF(0));
goto end;
}
if ((same_name= part_info->has_unique_names()))
{
my_error(ER_SAME_NAME_PARTITION, MYF(0), same_name);
goto end;
}
engine_array= (handlerton**)my_malloc(tot_partitions * sizeof(handlerton *),
MYF(MY_WME));
if (unlikely(!engine_array))
goto end;
i= 0;
no_parts= part_info->no_parts;
{
List_iterator<partition_element> part_it(part_info->partitions);
do
{
partition_element *part_elem= part_it++;
if (!part_info->is_sub_partitioned())
{
if (part_elem->engine_type == NULL)
part_elem->engine_type= part_info->default_engine_type;
DBUG_PRINT("info", ("engine = %d",
ha_legacy_type(part_elem->engine_type)));
engine_array[part_count++]= part_elem->engine_type;
}
else
{
uint j= 0, no_subparts= part_info->no_subparts;;
List_iterator<partition_element> sub_it(part_elem->subpartitions);
do
{
part_elem= sub_it++;
if (part_elem->engine_type == NULL)
part_elem->engine_type= part_info->default_engine_type;
DBUG_PRINT("info", ("engine = %u",
ha_legacy_type(part_elem->engine_type)));
engine_array[part_count++]= part_elem->engine_type;
} while (++j < no_subparts);
}
} while (++i < part_info->no_parts);
}
if (unlikely(check_engine_mix(engine_array, part_count)))
{
my_error(ER_MIX_HANDLER_ERROR, MYF(0));
goto end;
}
if (eng_type)
*eng_type= (handlerton*)engine_array[0];
/*
We need to check all constant expressions that they are of the correct
type and that they are increasing for ranges and not overlapping for
list constants.
*/
if (unlikely((part_info->part_type == RANGE_PARTITION &&
check_range_constants(part_info)) ||
(part_info->part_type == LIST_PARTITION &&
check_list_constants(part_info))))
goto end;
result= FALSE;
end:
my_free((char*)engine_array,MYF(MY_ALLOW_ZERO_PTR));
DBUG_RETURN(result);
}
/*
This method is used to set-up both partition and subpartitioning
field array and used for all types of partitioning.
It is part of the logic around fix_partition_func.
SYNOPSIS
set_up_field_array()
table TABLE object for which partition fields are set-up
sub_part Is the table subpartitioned as well
RETURN VALUE
TRUE Error, some field didn't meet requirements
FALSE Ok, partition field array set-up
DESCRIPTION
A great number of functions below here is part of the fix_partition_func
method. It is used to set up the partition structures for execution from
openfrm. It is called at the end of the openfrm when the table struct has
been set-up apart from the partition information.
It involves:
1) Setting arrays of fields for the partition functions.
2) Setting up binary search array for LIST partitioning
3) Setting up array for binary search for RANGE partitioning
4) Setting up key_map's to assist in quick evaluation whether one
can deduce anything from a given index of what partition to use
5) Checking whether a set of partitions can be derived from a range on
a field in the partition function.
As part of doing this there is also a great number of error controls.
This is actually the place where most of the things are checked for
partition information when creating a table.
Things that are checked includes
1) All fields of partition function in Primary keys and unique indexes
(if not supported)
Create an array of partition fields (NULL terminated). Before this method
is called fix_fields or find_table_in_sef has been called to set
GET_FIXED_FIELDS_FLAG on all fields that are part of the partition
function.
*/
static bool set_up_field_array(TABLE *table,
bool is_sub_part)
{
Field **ptr, *field, **field_array;
uint no_fields= 0;
uint size_field_array;
uint i= 0;
partition_info *part_info= table->part_info;
int result= FALSE;
DBUG_ENTER("set_up_field_array");
ptr= table->field;
while ((field= *(ptr++)))
{
if (field->flags & GET_FIXED_FIELDS_FLAG)
no_fields++;
}
if (no_fields == 0)
{
/*
We are using hidden key as partitioning field
*/
DBUG_ASSERT(!is_sub_part);
DBUG_RETURN(result);
}
size_field_array= (no_fields+1)*sizeof(Field*);
field_array= (Field**)sql_alloc(size_field_array);
if (unlikely(!field_array))
{
mem_alloc_error(size_field_array);
result= TRUE;
}
ptr= table->field;
while ((field= *(ptr++)))
{
if (field->flags & GET_FIXED_FIELDS_FLAG)
{
field->flags&= ~GET_FIXED_FIELDS_FLAG;
field->flags|= FIELD_IN_PART_FUNC_FLAG;
if (likely(!result))
{
field_array[i++]= field;
/*
We check that the fields are proper. It is required for each
field in a partition function to:
1) Not be a BLOB of any type
A BLOB takes too long time to evaluate so we don't want it for
performance reasons.
*/
if (unlikely(field->flags & BLOB_FLAG))
{
my_error(ER_BLOB_FIELD_IN_PART_FUNC_ERROR, MYF(0));
result= TRUE;
}
}
}
}
field_array[no_fields]= 0;
if (!is_sub_part)
{
part_info->part_field_array= field_array;
part_info->no_part_fields= no_fields;
}
else
{
part_info->subpart_field_array= field_array;
part_info->no_subpart_fields= no_fields;
}
DBUG_RETURN(result);
}
/*
Create a field array including all fields of both the partitioning and the
subpartitioning functions.
SYNOPSIS
create_full_part_field_array()
table TABLE object for which partition fields are set-up
part_info Reference to partitioning data structure
RETURN VALUE
TRUE Memory allocation of field array failed
FALSE Ok
DESCRIPTION
If there is no subpartitioning then the same array is used as for the
partitioning. Otherwise a new array is built up using the flag
FIELD_IN_PART_FUNC in the field object.
This function is called from fix_partition_func
*/
static bool create_full_part_field_array(TABLE *table,
partition_info *part_info)
{
bool result= FALSE;
DBUG_ENTER("create_full_part_field_array");
if (!part_info->is_sub_partitioned())
{
part_info->full_part_field_array= part_info->part_field_array;
part_info->no_full_part_fields= part_info->no_part_fields;
}
else
{
Field **ptr, *field, **field_array;
uint no_part_fields=0, size_field_array;
ptr= table->field;
while ((field= *(ptr++)))
{
if (field->flags & FIELD_IN_PART_FUNC_FLAG)
no_part_fields++;
}
size_field_array= (no_part_fields+1)*sizeof(Field*);
field_array= (Field**)sql_alloc(size_field_array);
if (unlikely(!field_array))
{
mem_alloc_error(size_field_array);
result= TRUE;
goto end;
}
no_part_fields= 0;
ptr= table->field;
while ((field= *(ptr++)))
{
if (field->flags & FIELD_IN_PART_FUNC_FLAG)
field_array[no_part_fields++]= field;
}
field_array[no_part_fields]=0;
part_info->full_part_field_array= field_array;
part_info->no_full_part_fields= no_part_fields;
}
end:
DBUG_RETURN(result);
}
/*
Clear flag GET_FIXED_FIELDS_FLAG in all fields of a key previously set by
set_indicator_in_key_fields (always used in pairs).
SYNOPSIS
clear_indicator_in_key_fields()
key_info Reference to find the key fields
RETURN VALUE
NONE
DESCRIPTION
These support routines is used to set/reset an indicator of all fields
in a certain key. It is used in conjunction with another support routine
that traverse all fields in the PF to find if all or some fields in the
PF is part of the key. This is used to check primary keys and unique
keys involve all fields in PF (unless supported) and to derive the
key_map's used to quickly decide whether the index can be used to
derive which partitions are needed to scan.
*/
static void clear_indicator_in_key_fields(KEY *key_info)
{
KEY_PART_INFO *key_part;
uint key_parts= key_info->key_parts, i;
for (i= 0, key_part=key_info->key_part; i < key_parts; i++, key_part++)
key_part->field->flags&= (~GET_FIXED_FIELDS_FLAG);
}
/*
Set flag GET_FIXED_FIELDS_FLAG in all fields of a key.
SYNOPSIS
set_indicator_in_key_fields
key_info Reference to find the key fields
RETURN VALUE
NONE
*/
static void set_indicator_in_key_fields(KEY *key_info)
{
KEY_PART_INFO *key_part;
uint key_parts= key_info->key_parts, i;
for (i= 0, key_part=key_info->key_part; i < key_parts; i++, key_part++)
key_part->field->flags|= GET_FIXED_FIELDS_FLAG;
}
/*
Check if all or some fields in partition field array is part of a key
previously used to tag key fields.
SYNOPSIS
check_fields_in_PF()
ptr Partition field array
out:all_fields Is all fields of partition field array used in key
out:some_fields Is some fields of partition field array used in key
RETURN VALUE
all_fields, some_fields
*/
static void check_fields_in_PF(Field **ptr, bool *all_fields,
bool *some_fields)
{
DBUG_ENTER("check_fields_in_PF");
*all_fields= TRUE;
*some_fields= FALSE;
if ((!ptr) || !(*ptr))
{
*all_fields= FALSE;
DBUG_VOID_RETURN;
}
do
{
/* Check if the field of the PF is part of the current key investigated */
if ((*ptr)->flags & GET_FIXED_FIELDS_FLAG)
*some_fields= TRUE;
else
*all_fields= FALSE;
} while (*(++ptr));
DBUG_VOID_RETURN;
}
/*
Clear flag GET_FIXED_FIELDS_FLAG in all fields of the table.
This routine is used for error handling purposes.
SYNOPSIS
clear_field_flag()
table TABLE object for which partition fields are set-up
RETURN VALUE
NONE
*/
static void clear_field_flag(TABLE *table)
{
Field **ptr;
DBUG_ENTER("clear_field_flag");
for (ptr= table->field; *ptr; ptr++)
(*ptr)->flags&= (~GET_FIXED_FIELDS_FLAG);
DBUG_VOID_RETURN;
}
/*
find_field_in_table_sef finds the field given its name. All fields get
GET_FIXED_FIELDS_FLAG set.
SYNOPSIS
handle_list_of_fields()
it A list of field names for the partition function
table TABLE object for which partition fields are set-up
part_info Reference to partitioning data structure
sub_part Is the table subpartitioned as well
RETURN VALUE
TRUE Fields in list of fields not part of table
FALSE All fields ok and array created
DESCRIPTION
This routine sets-up the partition field array for KEY partitioning, it
also verifies that all fields in the list of fields is actually a part of
the table.
*/
static bool handle_list_of_fields(List_iterator<char> it,
TABLE *table,
partition_info *part_info,
bool is_sub_part)
{
Field *field;
bool result;
char *field_name;
bool is_list_empty= TRUE;
DBUG_ENTER("handle_list_of_fields");
while ((field_name= it++))
{
is_list_empty= FALSE;
field= find_field_in_table_sef(table, field_name);
if (likely(field != 0))
field->flags|= GET_FIXED_FIELDS_FLAG;
else
{
my_error(ER_FIELD_NOT_FOUND_PART_ERROR, MYF(0));
clear_field_flag(table);
result= TRUE;
goto end;
}
}
if (is_list_empty)
{
uint primary_key= table->s->primary_key;
if (primary_key != MAX_KEY)
{
uint no_key_parts= table->key_info[primary_key].key_parts, i;
/*
In the case of an empty list we use primary key as partition key.
*/
for (i= 0; i < no_key_parts; i++)
{
Field *field= table->key_info[primary_key].key_part[i].field;
field->flags|= GET_FIXED_FIELDS_FLAG;
}
}
else
{
if (table->s->db_type->partition_flags &&
(table->s->db_type->partition_flags() & HA_USE_AUTO_PARTITION) &&
(table->s->db_type->partition_flags() & HA_CAN_PARTITION))
{
/*
This engine can handle automatic partitioning and there is no
primary key. In this case we rely on that the engine handles
partitioning based on a hidden key. Thus we allocate no
array for partitioning fields.
*/
DBUG_RETURN(FALSE);
}
else
{
my_error(ER_FIELD_NOT_FOUND_PART_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
}
}
result= set_up_field_array(table, is_sub_part);
end:
DBUG_RETURN(result);
}
/*
The function uses a new feature in fix_fields where the flag
GET_FIXED_FIELDS_FLAG is set for all fields in the item tree.
This field must always be reset before returning from the function
since it is used for other purposes as well.
SYNOPSIS
fix_fields_part_func()
thd The thread object
tables A list of one table, the partitioned table
func_expr The item tree reference of the partition function
part_info Reference to partitioning data structure
sub_part Is the table subpartitioned as well
RETURN VALUE
TRUE An error occurred, something was wrong with the
partition function.
FALSE Ok, a partition field array was created
DESCRIPTION
This function is used to build an array of partition fields for the
partitioning function and subpartitioning function. The partitioning
function is an item tree that must reference at least one field in the
table. This is checked first in the parser that the function doesn't
contain non-cacheable parts (like a random function) and by checking
here that the function isn't a constant function.
Calculate the number of fields in the partition function.
Use it allocate memory for array of Field pointers.
Initialise array of field pointers. Use information set when
calling fix_fields and reset it immediately after.
The get_fields_in_item_tree activates setting of bit in flags
on the field object.
*/
static bool fix_fields_part_func(THD *thd, TABLE_LIST *tables,
Item* func_expr, partition_info *part_info,
bool is_sub_part)
{
bool result= TRUE;
TABLE *table= tables->table;
TABLE_LIST *save_table_list, *save_first_table, *save_last_table;
int error;
Name_resolution_context *context;
const char *save_where;
DBUG_ENTER("fix_fields_part_func");
context= thd->lex->current_context();
table->map= 1; //To ensure correct calculation of const item
table->get_fields_in_item_tree= TRUE;
save_table_list= context->table_list;
save_first_table= context->first_name_resolution_table;
save_last_table= context->last_name_resolution_table;
context->table_list= tables;
context->first_name_resolution_table= tables;
context->last_name_resolution_table= NULL;
func_expr->walk(&Item::change_context_processor, (byte*) context);
save_where= thd->where;
thd->where= "partition function";
error= func_expr->fix_fields(thd, (Item**)0);
context->table_list= save_table_list;
context->first_name_resolution_table= save_first_table;
context->last_name_resolution_table= save_last_table;
if (unlikely(error))
{
DBUG_PRINT("info", ("Field in partition function not part of table"));
clear_field_flag(table);
goto end;
}
thd->where= save_where;
if (unlikely(func_expr->const_item()))
{
my_error(ER_CONST_EXPR_IN_PARTITION_FUNC_ERROR, MYF(0));
clear_field_flag(table);
goto end;
}
result= set_up_field_array(table, is_sub_part);
end:
table->get_fields_in_item_tree= FALSE;
table->map= 0; //Restore old value
DBUG_RETURN(result);
}
/*
Check that the primary key contains all partition fields if defined
SYNOPSIS
check_primary_key()
table TABLE object for which partition fields are set-up
RETURN VALUES
TRUE Not all fields in partitioning function was part
of primary key
FALSE Ok, all fields of partitioning function were part
of primary key
DESCRIPTION
This function verifies that if there is a primary key that it contains
all the fields of the partition function.
This is a temporary limitation that will hopefully be removed after a
while.
*/
static bool check_primary_key(TABLE *table)
{
uint primary_key= table->s->primary_key;
bool all_fields, some_fields;
bool result= FALSE;
DBUG_ENTER("check_primary_key");
if (primary_key < MAX_KEY)
{
set_indicator_in_key_fields(table->key_info+primary_key);
check_fields_in_PF(table->part_info->full_part_field_array,
&all_fields, &some_fields);
clear_indicator_in_key_fields(table->key_info+primary_key);
if (unlikely(!all_fields))
{
my_error(ER_UNIQUE_KEY_NEED_ALL_FIELDS_IN_PF,MYF(0),"PRIMARY KEY");
result= TRUE;
}
}
DBUG_RETURN(result);
}
/*
Check that unique keys contains all partition fields
SYNOPSIS
check_unique_keys()
table TABLE object for which partition fields are set-up
RETURN VALUES
TRUE Not all fields in partitioning function was part
of all unique keys
FALSE Ok, all fields of partitioning function were part
of unique keys
DESCRIPTION
This function verifies that if there is a unique index that it contains
all the fields of the partition function.
This is a temporary limitation that will hopefully be removed after a
while.
*/
static bool check_unique_keys(TABLE *table)
{
bool all_fields, some_fields;
bool result= FALSE;
uint keys= table->s->keys;
uint i;
DBUG_ENTER("check_unique_keys");
for (i= 0; i < keys; i++)
{
if (table->key_info[i].flags & HA_NOSAME) //Unique index
{
set_indicator_in_key_fields(table->key_info+i);
check_fields_in_PF(table->part_info->full_part_field_array,
&all_fields, &some_fields);
clear_indicator_in_key_fields(table->key_info+i);
if (unlikely(!all_fields))
{
my_error(ER_UNIQUE_KEY_NEED_ALL_FIELDS_IN_PF,MYF(0),"UNIQUE INDEX");
result= TRUE;
break;
}
}
}
DBUG_RETURN(result);
}
/*
An important optimisation is whether a range on a field can select a subset
of the partitions.
A prerequisite for this to happen is that the PF is a growing function OR
a shrinking function.
This can never happen for a multi-dimensional PF. Thus this can only happen
with PF with at most one field involved in the PF.
The idea is that if the function is a growing function and you know that
the field of the PF is 4 <= A <= 6 then we can convert this to a range
in the PF instead by setting the range to PF(4) <= PF(A) <= PF(6). In the
case of RANGE PARTITIONING and LIST PARTITIONING this can be used to
calculate a set of partitions rather than scanning all of them.
Thus the following prerequisites are there to check if sets of partitions
can be found.
1) Only possible for RANGE and LIST partitioning (not for subpartitioning)
2) Only possible if PF only contains 1 field
3) Possible if PF is a growing function of the field
4) Possible if PF is a shrinking function of the field
OBSERVATION:
1) IF f1(A) is a growing function AND f2(A) is a growing function THEN
f1(A) + f2(A) is a growing function
f1(A) * f2(A) is a growing function if f1(A) >= 0 and f2(A) >= 0
2) IF f1(A) is a growing function and f2(A) is a shrinking function THEN
f1(A) / f2(A) is a growing function if f1(A) >= 0 and f2(A) > 0
3) IF A is a growing function then a function f(A) that removes the
least significant portion of A is a growing function
E.g. DATE(datetime) is a growing function
MONTH(datetime) is not a growing/shrinking function
4) IF f1(A) is a growing function and f2(A) is a growing function THEN
f1(f2(A)) and f2(f1(A)) are also growing functions
5) IF f1(A) is a shrinking function and f2(A) is a growing function THEN
f1(f2(A)) is a shrinking function and f2(f1(A)) is a shrinking function
6) f1(A) = A is a growing function
7) f1(A) = A*a + b (where a and b are constants) is a growing function
By analysing the item tree of the PF we can use these deducements and
derive whether the PF is a growing function or a shrinking function or
neither of it.
If the PF is range capable then a flag is set on the table object
indicating this to notify that we can use also ranges on the field
of the PF to deduce a set of partitions if the fields of the PF were
not all fully bound.
SYNOPSIS
check_range_capable_PF()
table TABLE object for which partition fields are set-up
DESCRIPTION
Support for this is not implemented yet.
*/
void check_range_capable_PF(TABLE *table)
{
DBUG_ENTER("check_range_capable_PF");
DBUG_VOID_RETURN;
}
/*
Set up partition bitmap
SYNOPSIS
set_up_partition_bitmap()
thd Thread object
part_info Reference to partitioning data structure
RETURN VALUE
TRUE Memory allocation failure
FALSE Success
DESCRIPTION
Allocate memory for bitmap of the partitioned table
and initialise it.
*/
static bool set_up_partition_bitmap(THD *thd, partition_info *part_info)
{
uint32 *bitmap_buf;
uint bitmap_bits= part_info->no_subparts?
(part_info->no_subparts* part_info->no_parts):
part_info->no_parts;
uint bitmap_bytes= bitmap_buffer_size(bitmap_bits);
DBUG_ENTER("set_up_partition_bitmap");
if (!(bitmap_buf= (uint32*)thd->alloc(bitmap_bytes)))
{
mem_alloc_error(bitmap_bytes);
DBUG_RETURN(TRUE);
}
bitmap_init(&part_info->used_partitions, bitmap_buf, bitmap_bytes*8, FALSE);
DBUG_RETURN(FALSE);
}
/*
Set up partition key maps
SYNOPSIS
set_up_partition_key_maps()
table TABLE object for which partition fields are set-up
part_info Reference to partitioning data structure
RETURN VALUES
None
DESCRIPTION
This function sets up a couple of key maps to be able to quickly check
if an index ever can be used to deduce the partition fields or even
a part of the fields of the partition function.
We set up the following key_map's.
PF = Partition Function
1) All fields of the PF is set even by equal on the first fields in the
key
2) All fields of the PF is set if all fields of the key is set
3) At least one field in the PF is set if all fields is set
4) At least one field in the PF is part of the key
*/
static void set_up_partition_key_maps(TABLE *table,
partition_info *part_info)
{
uint keys= table->s->keys;
uint i;
bool all_fields, some_fields;
DBUG_ENTER("set_up_partition_key_maps");
part_info->all_fields_in_PF.clear_all();
part_info->all_fields_in_PPF.clear_all();
part_info->all_fields_in_SPF.clear_all();
part_info->some_fields_in_PF.clear_all();
for (i= 0; i < keys; i++)
{
set_indicator_in_key_fields(table->key_info+i);
check_fields_in_PF(part_info->full_part_field_array,
&all_fields, &some_fields);
if (all_fields)
part_info->all_fields_in_PF.set_bit(i);
if (some_fields)
part_info->some_fields_in_PF.set_bit(i);
if (part_info->is_sub_partitioned())
{
check_fields_in_PF(part_info->part_field_array,
&all_fields, &some_fields);
if (all_fields)
part_info->all_fields_in_PPF.set_bit(i);
check_fields_in_PF(part_info->subpart_field_array,
&all_fields, &some_fields);
if (all_fields)
part_info->all_fields_in_SPF.set_bit(i);
}
clear_indicator_in_key_fields(table->key_info+i);
}
DBUG_VOID_RETURN;
}
/*
Set up function pointers for partition function
SYNOPSIS
set_up_partition_func_pointers()
part_info Reference to partitioning data structure
RETURN VALUE
NONE
DESCRIPTION
Set-up all function pointers for calculation of partition id,
subpartition id and the upper part in subpartitioning. This is to speed up
execution of get_partition_id which is executed once every record to be
written and deleted and twice for updates.
*/
static void set_up_partition_func_pointers(partition_info *part_info)
{
DBUG_ENTER("set_up_partition_func_pointers");
if (part_info->is_sub_partitioned())
{
if (part_info->part_type == RANGE_PARTITION)
{
part_info->get_part_partition_id= get_partition_id_range;
if (part_info->list_of_subpart_fields)
{
if (part_info->linear_hash_ind)
{
part_info->get_partition_id= get_partition_id_range_sub_linear_key;
part_info->get_subpartition_id= get_partition_id_linear_key_sub;
}
else
{
part_info->get_partition_id= get_partition_id_range_sub_key;
part_info->get_subpartition_id= get_partition_id_key_sub;
}
}
else
{
if (part_info->linear_hash_ind)
{
part_info->get_partition_id= get_partition_id_range_sub_linear_hash;
part_info->get_subpartition_id= get_partition_id_linear_hash_sub;
}
else
{
part_info->get_partition_id= get_partition_id_range_sub_hash;
part_info->get_subpartition_id= get_partition_id_hash_sub;
}
}
}
else /* LIST Partitioning */
{
part_info->get_part_partition_id= get_partition_id_list;
if (part_info->list_of_subpart_fields)
{
if (part_info->linear_hash_ind)
{
part_info->get_partition_id= get_partition_id_list_sub_linear_key;
part_info->get_subpartition_id= get_partition_id_linear_key_sub;
}
else
{
part_info->get_partition_id= get_partition_id_list_sub_key;
part_info->get_subpartition_id= get_partition_id_key_sub;
}
}
else
{
if (part_info->linear_hash_ind)
{
part_info->get_partition_id= get_partition_id_list_sub_linear_hash;
part_info->get_subpartition_id= get_partition_id_linear_hash_sub;
}
else
{
part_info->get_partition_id= get_partition_id_list_sub_hash;
part_info->get_subpartition_id= get_partition_id_hash_sub;
}
}
}
}
else /* No subpartitioning */
{
part_info->get_part_partition_id= NULL;
part_info->get_subpartition_id= NULL;
if (part_info->part_type == RANGE_PARTITION)
part_info->get_partition_id= get_partition_id_range;
else if (part_info->part_type == LIST_PARTITION)
part_info->get_partition_id= get_partition_id_list;
else /* HASH partitioning */
{
if (part_info->list_of_part_fields)
{
if (part_info->linear_hash_ind)
part_info->get_partition_id= get_partition_id_linear_key_nosub;
else
part_info->get_partition_id= get_partition_id_key_nosub;
}
else
{
if (part_info->linear_hash_ind)
part_info->get_partition_id= get_partition_id_linear_hash_nosub;
else
part_info->get_partition_id= get_partition_id_hash_nosub;
}
}
}
DBUG_VOID_RETURN;
}
/*
For linear hashing we need a mask which is on the form 2**n - 1 where
2**n >= no_parts. Thus if no_parts is 6 then mask is 2**3 - 1 = 8 - 1 = 7.
SYNOPSIS
set_linear_hash_mask()
part_info Reference to partitioning data structure
no_parts Number of parts in linear hash partitioning
RETURN VALUE
NONE
*/
static void set_linear_hash_mask(partition_info *part_info, uint no_parts)
{
uint mask;
for (mask= 1; mask < no_parts; mask<<=1)
;
part_info->linear_hash_mask= mask - 1;
}
/*
This function calculates the partition id provided the result of the hash
function using linear hashing parameters, mask and number of partitions.
SYNOPSIS
get_part_id_from_linear_hash()
hash_value Hash value calculated by HASH function or KEY function
mask Mask calculated previously by set_linear_hash_mask
no_parts Number of partitions in HASH partitioned part
RETURN VALUE
part_id The calculated partition identity (starting at 0)
DESCRIPTION
The partition is calculated according to the theory of linear hashing.
See e.g. Linear hashing: a new tool for file and table addressing,
Reprinted from VLDB-80 in Readings Database Systems, 2nd ed, M. Stonebraker
(ed.), Morgan Kaufmann 1994.
*/
static uint32 get_part_id_from_linear_hash(longlong hash_value, uint mask,
uint no_parts)
{
uint32 part_id= (uint32)(hash_value & mask);
if (part_id >= no_parts)
{
uint new_mask= ((mask + 1) >> 1) - 1;
part_id= (uint32)(hash_value & new_mask);
}
return part_id;
}
/*
fix partition functions
SYNOPSIS
fix_partition_func()
thd The thread object
name The name of the partitioned table
table TABLE object for which partition fields are set-up
create_table_ind Indicator of whether openfrm was called as part of
CREATE or ALTER TABLE
RETURN VALUE
TRUE Error
FALSE Success
DESCRIPTION
The name parameter contains the full table name and is used to get the
database name of the table which is used to set-up a correct
TABLE_LIST object for use in fix_fields.
NOTES
This function is called as part of opening the table by opening the .frm
file. It is a part of CREATE TABLE to do this so it is quite permissible
that errors due to erroneus syntax isn't found until we come here.
If the user has used a non-existing field in the table is one such example
of an error that is not discovered until here.
*/
bool fix_partition_func(THD *thd, const char* name, TABLE *table,
bool is_create_table_ind)
{
bool result= TRUE;
uint dir_length, home_dir_length;
TABLE_LIST tables;
TABLE_SHARE *share= table->s;
char db_name_string[FN_REFLEN];
char* db_name;
partition_info *part_info= table->part_info;
ulong save_set_query_id= thd->set_query_id;
DBUG_ENTER("fix_partition_func");
if (part_info->fixed)
{
DBUG_RETURN(FALSE);
}
thd->set_query_id= 0;
DBUG_PRINT("info", ("thd->set_query_id: %d", thd->set_query_id));
/*
Set-up the TABLE_LIST object to be a list with a single table
Set the object to zero to create NULL pointers and set alias
and real name to table name and get database name from file name.
*/
bzero((void*)&tables, sizeof(TABLE_LIST));
tables.alias= tables.table_name= (char*) share->table_name.str;
tables.table= table;
tables.next_local= 0;
tables.next_name_resolution_table= 0;
strmov(db_name_string, name);
dir_length= dirname_length(db_name_string);
db_name_string[dir_length - 1]= 0;
home_dir_length= dirname_length(db_name_string);
db_name= &db_name_string[home_dir_length];
tables.db= db_name;
if (!is_create_table_ind)
{
if (partition_default_handling(table, part_info,
table->s->normalized_path.str))
{
DBUG_RETURN(TRUE);
}
}
if (part_info->is_sub_partitioned())
{
DBUG_ASSERT(part_info->subpart_type == HASH_PARTITION);
/*
Subpartition is defined. We need to verify that subpartitioning
function is correct.
*/
if (part_info->linear_hash_ind)
set_linear_hash_mask(part_info, part_info->no_subparts);
if (part_info->list_of_subpart_fields)
{
List_iterator<char> it(part_info->subpart_field_list);
if (unlikely(handle_list_of_fields(it, table, part_info, TRUE)))
goto end;
}
else
{
if (unlikely(fix_fields_part_func(thd, &tables,
part_info->subpart_expr, part_info,
TRUE)))
goto end;
if (unlikely(part_info->subpart_expr->result_type() != INT_RESULT))
{
my_error(ER_PARTITION_FUNC_NOT_ALLOWED_ERROR, MYF(0),
"SUBPARTITION");
goto end;
}
}
}
DBUG_ASSERT(part_info->part_type != NOT_A_PARTITION);
/*
Partition is defined. We need to verify that partitioning
function is correct.
*/
if (part_info->part_type == HASH_PARTITION)
{
if (part_info->linear_hash_ind)
set_linear_hash_mask(part_info, part_info->no_parts);
if (part_info->list_of_part_fields)
{
List_iterator<char> it(part_info->part_field_list);
if (unlikely(handle_list_of_fields(it, table, part_info, FALSE)))
goto end;
}
else
{
if (unlikely(fix_fields_part_func(thd, &tables, part_info->part_expr,
part_info, FALSE)))
goto end;
if (unlikely(part_info->part_expr->result_type() != INT_RESULT))
{
my_error(ER_PARTITION_FUNC_NOT_ALLOWED_ERROR, MYF(0), part_str);
goto end;
}
part_info->part_result_type= INT_RESULT;
}
}
else
{
const char *error_str;
if (part_info->part_type == RANGE_PARTITION)
{
error_str= partition_keywords[PKW_RANGE].str;
if (unlikely(check_range_constants(part_info)))
goto end;
}
else if (part_info->part_type == LIST_PARTITION)
{
error_str= partition_keywords[PKW_LIST].str;
if (unlikely(check_list_constants(part_info)))
goto end;
}
else
{
DBUG_ASSERT(0);
my_error(ER_INCONSISTENT_PARTITION_INFO_ERROR, MYF(0));
goto end;
}
if (unlikely(part_info->no_parts < 1))
{
my_error(ER_PARTITIONS_MUST_BE_DEFINED_ERROR, MYF(0), error_str);
goto end;
}
if (unlikely(fix_fields_part_func(thd, &tables, part_info->part_expr,
part_info, FALSE)))
goto end;
if (unlikely(part_info->part_expr->result_type() != INT_RESULT))
{
my_error(ER_PARTITION_FUNC_NOT_ALLOWED_ERROR, MYF(0), part_str);
goto end;
}
}
if (unlikely(create_full_part_field_array(table, part_info)))
goto end;
if (unlikely(check_primary_key(table)))
goto end;
if (unlikely((!(table->s->db_type->partition_flags &&
(table->s->db_type->partition_flags() & HA_CAN_PARTITION_UNIQUE))) &&
check_unique_keys(table)))
goto end;
if (unlikely(set_up_partition_bitmap(thd, part_info)))
goto end;
check_range_capable_PF(table);
set_up_partition_key_maps(table, part_info);
set_up_partition_func_pointers(part_info);
part_info->fixed= TRUE;
set_up_range_analysis_info(part_info);
result= FALSE;
end:
thd->set_query_id= save_set_query_id;
DBUG_PRINT("info", ("thd->set_query_id: %d", thd->set_query_id));
DBUG_RETURN(result);
}
/*
The code below is support routines for the reverse parsing of the
partitioning syntax. This feature is very useful to generate syntax for
all default values to avoid all default checking when opening the frm
file. It is also used when altering the partitioning by use of various
ALTER TABLE commands. Finally it is used for SHOW CREATE TABLES.
*/
static int add_write(File fptr, const char *buf, uint len)
{
uint len_written= my_write(fptr, (const byte*)buf, len, MYF(0));
if (likely(len == len_written))
return 0;
else
return 1;
}
static int add_string(File fptr, const char *string)
{
return add_write(fptr, string, strlen(string));
}
static int add_string_len(File fptr, const char *string, uint len)
{
return add_write(fptr, string, len);
}
static int add_space(File fptr)
{
return add_string(fptr, space_str);
}
static int add_comma(File fptr)
{
return add_string(fptr, comma_str);
}
static int add_equal(File fptr)
{
return add_string(fptr, equal_str);
}
static int add_end_parenthesis(File fptr)
{
return add_string(fptr, end_paren_str);
}
static int add_begin_parenthesis(File fptr)
{
return add_string(fptr, begin_paren_str);
}
static int add_part_key_word(File fptr, const char *key_string)
{
int err= add_string(fptr, key_string);
err+= add_space(fptr);
return err + add_begin_parenthesis(fptr);
}
static int add_hash(File fptr)
{
return add_part_key_word(fptr, partition_keywords[PKW_HASH].str);
}
static int add_partition(File fptr)
{
strxmov(buff, part_str, space_str, NullS);
return add_string(fptr, buff);
}
static int add_subpartition(File fptr)
{
int err= add_string(fptr, sub_str);
return err + add_partition(fptr);
}
static int add_partition_by(File fptr)
{
strxmov(buff, part_str, space_str, by_str, space_str, NullS);
return add_string(fptr, buff);
}
static int add_subpartition_by(File fptr)
{
int err= add_string(fptr, sub_str);
return err + add_partition_by(fptr);
}
static int add_key_partition(File fptr, List<char> field_list)
{
uint i, no_fields;
int err;
List_iterator<char> part_it(field_list);
err= add_part_key_word(fptr, partition_keywords[PKW_KEY].str);
no_fields= field_list.elements;
i= 0;
while (i < no_fields)
{
const char *field_str= part_it++;
err+= add_string(fptr, field_str);
if (i != (no_fields-1))
err+= add_comma(fptr);
i++;
}
return err;
}
static int add_int(File fptr, longlong number)
{
llstr(number, buff);
return add_string(fptr, buff);
}
static int add_keyword_string(File fptr, const char *keyword,
bool should_use_quotes,
const char *keystr)
{
int err= add_string(fptr, keyword);
err+= add_space(fptr);
err+= add_equal(fptr);
err+= add_space(fptr);
if (should_use_quotes)
err+= add_string(fptr, "'");
err+= add_string(fptr, keystr);
if (should_use_quotes)
err+= add_string(fptr, "'");
return err + add_space(fptr);
}
static int add_keyword_int(File fptr, const char *keyword, longlong num)
{
int err= add_string(fptr, keyword);
err+= add_space(fptr);
err+= add_equal(fptr);
err+= add_space(fptr);
err+= add_int(fptr, num);
return err + add_space(fptr);
}
static int add_engine(File fptr, handlerton *engine_type)
{
const char *engine_str= engine_type->name;
DBUG_PRINT("info", ("ENGINE = %s", engine_str));
int err= add_string(fptr, "ENGINE = ");
return err + add_string(fptr, engine_str);
}
static int add_partition_options(File fptr, partition_element *p_elem)
{
int err= 0;
if (p_elem->tablespace_name)
err+= add_keyword_string(fptr,"TABLESPACE", FALSE,
p_elem->tablespace_name);
if (p_elem->nodegroup_id != UNDEF_NODEGROUP)
err+= add_keyword_int(fptr,"NODEGROUP",(longlong)p_elem->nodegroup_id);
if (p_elem->part_max_rows)
err+= add_keyword_int(fptr,"MAX_ROWS",(longlong)p_elem->part_max_rows);
if (p_elem->part_min_rows)
err+= add_keyword_int(fptr,"MIN_ROWS",(longlong)p_elem->part_min_rows);
if (p_elem->data_file_name)
err+= add_keyword_string(fptr, "DATA DIRECTORY", TRUE,
p_elem->data_file_name);
if (p_elem->index_file_name)
err+= add_keyword_string(fptr, "INDEX DIRECTORY", TRUE,
p_elem->index_file_name);
if (p_elem->part_comment)
err+= add_keyword_string(fptr, "COMMENT", FALSE, p_elem->part_comment);
return err + add_engine(fptr,p_elem->engine_type);
}
static int add_partition_values(File fptr, partition_info *part_info,
partition_element *p_elem)
{
int err= 0;
if (part_info->part_type == RANGE_PARTITION)
{
err+= add_string(fptr, "VALUES LESS THAN ");
if (p_elem->range_value != LONGLONG_MAX)
{
err+= add_begin_parenthesis(fptr);
err+= add_int(fptr, p_elem->range_value);
err+= add_end_parenthesis(fptr);
}
else
err+= add_string(fptr, partition_keywords[PKW_MAXVALUE].str);
}
else if (part_info->part_type == LIST_PARTITION)
{
uint i;
List_iterator<longlong> list_val_it(p_elem->list_val_list);
err+= add_string(fptr, "VALUES IN ");
uint no_items= p_elem->list_val_list.elements;
err+= add_begin_parenthesis(fptr);
i= 0;
do
{
longlong *list_value= list_val_it++;
err+= add_int(fptr, *list_value);
if (i != (no_items-1))
err+= add_comma(fptr);
} while (++i < no_items);
err+= add_end_parenthesis(fptr);
}
return err + add_space(fptr);
}
/*
Generate the partition syntax from the partition data structure.
Useful for support of generating defaults, SHOW CREATE TABLES
and easy partition management.
SYNOPSIS
generate_partition_syntax()
part_info The partitioning data structure
buf_length A pointer to the returned buffer length
use_sql_alloc Allocate buffer from sql_alloc if true
otherwise use my_malloc
write_all Write everything, also default values
RETURN VALUES
NULL error
buf, buf_length Buffer and its length
DESCRIPTION
Here we will generate the full syntax for the given command where all
defaults have been expanded. By so doing the it is also possible to
make lots of checks of correctness while at it.
This could will also be reused for SHOW CREATE TABLES and also for all
type ALTER TABLE commands focusing on changing the PARTITION structure
in any fashion.
The implementation writes the syntax to a temporary file (essentially
an abstraction of a dynamic array) and if all writes goes well it
allocates a buffer and writes the syntax into this one and returns it.
As a security precaution the file is deleted before writing into it. This
means that no other processes on the machine can open and read the file
while this processing is ongoing.
The code is optimised for minimal code size since it is not used in any
common queries.
*/
char *generate_partition_syntax(partition_info *part_info,
uint *buf_length,
bool use_sql_alloc,
bool write_all)
{
uint i,j, tot_no_parts, no_subparts, no_parts;
partition_element *part_elem;
partition_element *save_part_elem= NULL;
ulonglong buffer_length;
char path[FN_REFLEN];
int err= 0;
List_iterator<partition_element> part_it(part_info->partitions);
List_iterator<partition_element> temp_it(part_info->temp_partitions);
File fptr;
char *buf= NULL; //Return buffer
uint use_temp= 0;
uint no_temp_parts= part_info->temp_partitions.elements;
bool write_part_state;
DBUG_ENTER("generate_partition_syntax");
write_part_state= (part_info->part_state && !part_info->part_state_len);
if (unlikely(((fptr= create_temp_file(path,mysql_tmpdir,"psy",
O_RDWR | O_BINARY | O_TRUNC |
O_TEMPORARY, MYF(MY_WME)))) < 0))
DBUG_RETURN(NULL);
#ifndef __WIN__
unlink(path);
#endif
err+= add_space(fptr);
err+= add_partition_by(fptr);
switch (part_info->part_type)
{
case RANGE_PARTITION:
err+= add_part_key_word(fptr, partition_keywords[PKW_RANGE].str);
break;
case LIST_PARTITION:
err+= add_part_key_word(fptr, partition_keywords[PKW_LIST].str);
break;
case HASH_PARTITION:
if (part_info->linear_hash_ind)
err+= add_string(fptr, partition_keywords[PKW_LINEAR].str);
if (part_info->list_of_part_fields)
err+= add_key_partition(fptr, part_info->part_field_list);
else
err+= add_hash(fptr);
break;
default:
DBUG_ASSERT(0);
/* We really shouldn't get here, no use in continuing from here */
current_thd->fatal_error();
DBUG_RETURN(NULL);
}
if (part_info->part_expr)
err+= add_string_len(fptr, part_info->part_func_string,
part_info->part_func_len);
err+= add_end_parenthesis(fptr);
err+= add_space(fptr);
if ((!part_info->use_default_no_partitions) &&
part_info->use_default_partitions)
{
err+= add_string(fptr, "PARTITIONS ");
err+= add_int(fptr, part_info->no_parts);
err+= add_space(fptr);
}
if (part_info->is_sub_partitioned())
{
err+= add_subpartition_by(fptr);
/* Must be hash partitioning for subpartitioning */
if (part_info->list_of_subpart_fields)
err+= add_key_partition(fptr, part_info->subpart_field_list);
else
err+= add_hash(fptr);
if (part_info->subpart_expr)
err+= add_string_len(fptr, part_info->subpart_func_string,
part_info->subpart_func_len);
err+= add_end_parenthesis(fptr);
err+= add_space(fptr);
if ((!part_info->use_default_no_subpartitions) &&
part_info->use_default_subpartitions)
{
err+= add_string(fptr, "SUBPARTITIONS ");
err+= add_int(fptr, part_info->no_subparts);
err+= add_space(fptr);
}
}
no_parts= part_info->no_parts;
tot_no_parts= no_parts + no_temp_parts;
no_subparts= part_info->no_subparts;
if (write_all || (!part_info->use_default_partitions))
{
err+= add_begin_parenthesis(fptr);
i= 0;
do
{
/*
We need to do some clever list manipulation here since we have two
different needs for our list processing and here we take some of the
cost of using a simpler list processing for the other parts of the
code.
ALTER TABLE REORGANIZE PARTITIONS has the list of partitions to be
the final list as the main list and the reorganised partitions is in
the temporary partition list. Thus when finding the first part added
we insert the temporary list if there is such a list. If there is no
temporary list we are performing an ADD PARTITION.
*/
if (use_temp && use_temp <= no_temp_parts)
{
part_elem= temp_it++;
DBUG_ASSERT(no_temp_parts);
no_temp_parts--;
}
else if (use_temp)
{
DBUG_ASSERT(no_parts);
part_elem= save_part_elem;
use_temp= 0;
no_parts--;
}
else
{
part_elem= part_it++;
if ((part_elem->part_state == PART_TO_BE_ADDED ||
part_elem->part_state == PART_IS_ADDED) && no_temp_parts)
{
save_part_elem= part_elem;
part_elem= temp_it++;
no_temp_parts--;
use_temp= 1;
}
else
{
DBUG_ASSERT(no_parts);
no_parts--;
}
}
if (part_elem->part_state != PART_IS_DROPPED)
{
if (write_part_state)
{
uint32 part_state_id= part_info->part_state_len;
part_info->part_state[part_state_id]= (uchar)part_elem->part_state;
part_info->part_state_len= part_state_id+1;
}
err+= add_partition(fptr);
err+= add_string(fptr, part_elem->partition_name);
err+= add_space(fptr);
err+= add_partition_values(fptr, part_info, part_elem);
if (!part_info->is_sub_partitioned())
err+= add_partition_options(fptr, part_elem);
if (part_info->is_sub_partitioned() &&
(write_all || (!part_info->use_default_subpartitions)))
{
err+= add_space(fptr);
err+= add_begin_parenthesis(fptr);
List_iterator<partition_element> sub_it(part_elem->subpartitions);
j= 0;
do
{
part_elem= sub_it++;
err+= add_subpartition(fptr);
err+= add_string(fptr, part_elem->partition_name);
err+= add_space(fptr);
err+= add_partition_options(fptr, part_elem);
if (j != (no_subparts-1))
{
err+= add_comma(fptr);
err+= add_space(fptr);
}
else
err+= add_end_parenthesis(fptr);
} while (++j < no_subparts);
}
if (i != (tot_no_parts-1))
{
err+= add_comma(fptr);
err+= add_space(fptr);
}
}
if (i == (tot_no_parts-1))
err+= add_end_parenthesis(fptr);
} while (++i < tot_no_parts);
DBUG_ASSERT(!no_parts && !no_temp_parts);
}
if (err)
goto close_file;
buffer_length= my_seek(fptr, 0L,MY_SEEK_END,MYF(0));
if (unlikely(buffer_length == MY_FILEPOS_ERROR))
goto close_file;
if (unlikely(my_seek(fptr, 0L, MY_SEEK_SET, MYF(0)) == MY_FILEPOS_ERROR))
goto close_file;
*buf_length= (uint)buffer_length;
if (use_sql_alloc)
buf= sql_alloc(*buf_length+1);
else
buf= my_malloc(*buf_length+1, MYF(MY_WME));
if (!buf)
goto close_file;
if (unlikely(my_read(fptr, (byte*)buf, *buf_length, MYF(MY_FNABP))))
{
if (!use_sql_alloc)
my_free(buf, MYF(0));
else
buf= NULL;
}
else
buf[*buf_length]= 0;
close_file:
my_close(fptr, MYF(0));
DBUG_RETURN(buf);
}
/*
Check if partition key fields are modified and if it can be handled by the
underlying storage engine.
SYNOPSIS
partition_key_modified
table TABLE object for which partition fields are set-up
fields A list of the to be modifed
RETURN VALUES
TRUE Need special handling of UPDATE
FALSE Normal UPDATE handling is ok
*/
bool partition_key_modified(TABLE *table, List<Item> &fields)
{
List_iterator_fast<Item> f(fields);
partition_info *part_info= table->part_info;
Item_field *item_field;
DBUG_ENTER("partition_key_modified");
if (!part_info)
DBUG_RETURN(FALSE);
if (table->s->db_type->partition_flags &&
(table->s->db_type->partition_flags() & HA_CAN_UPDATE_PARTITION_KEY))
DBUG_RETURN(FALSE);
f.rewind();
while ((item_field=(Item_field*) f++))
if (item_field->field->flags & FIELD_IN_PART_FUNC_FLAG)
DBUG_RETURN(TRUE);
DBUG_RETURN(FALSE);
}
/*
The next set of functions are used to calculate the partition identity.
A handler sets up a variable that corresponds to one of these functions
to be able to quickly call it whenever the partition id needs to calculated
based on the record in table->record[0] (or set up to fake that).
There are 4 functions for hash partitioning and 2 for RANGE/LIST partitions.
In addition there are 4 variants for RANGE subpartitioning and 4 variants
for LIST subpartitioning thus in total there are 14 variants of this
function.
We have a set of support functions for these 14 variants. There are 4
variants of hash functions and there is a function for each. The KEY
partitioning uses the function calculate_key_value to calculate the hash
value based on an array of fields. The linear hash variants uses the
method get_part_id_from_linear_hash to get the partition id using the
hash value and some parameters calculated from the number of partitions.
*/
/*
Calculate hash value for KEY partitioning using an array of fields.
SYNOPSIS
calculate_key_value()
field_array An array of the fields in KEY partitioning
RETURN VALUE
hash_value calculated
DESCRIPTION
Uses the hash function on the character set of the field. Integer and
floating point fields use the binary character set by default.
*/
static uint32 calculate_key_value(Field **field_array)
{
uint32 hashnr= 0;
ulong nr2= 4;
do
{
Field *field= *field_array;
if (field->is_null())
{
hashnr^= (hashnr << 1) | 1;
}
else
{
uint len= field->pack_length();
ulong nr1= 1;
CHARSET_INFO *cs= field->charset();
cs->coll->hash_sort(cs, (uchar*)field->ptr, len, &nr1, &nr2);
hashnr^= (uint32)nr1;
}
} while (*(++field_array));
return hashnr;
}
/*
A simple support function to calculate part_id given local part and
sub part.
SYNOPSIS
get_part_id_for_sub()
loc_part_id Local partition id
sub_part_id Subpartition id
no_subparts Number of subparts
*/
inline
static uint32 get_part_id_for_sub(uint32 loc_part_id, uint32 sub_part_id,
uint no_subparts)
{
return (uint32)((loc_part_id * no_subparts) + sub_part_id);
}
/*
Calculate part_id for (SUB)PARTITION BY HASH
SYNOPSIS
get_part_id_hash()
no_parts Number of hash partitions
part_expr Item tree of hash function
out:func_value Value of hash function
RETURN VALUE
Calculated partition id
*/
inline
static uint32 get_part_id_hash(uint no_parts,
Item *part_expr,
longlong *func_value)
{
DBUG_ENTER("get_part_id_hash");
*func_value= part_expr->val_int();
longlong int_hash_id= *func_value % no_parts;
DBUG_RETURN(int_hash_id < 0 ? -int_hash_id : int_hash_id);
}
/*
Calculate part_id for (SUB)PARTITION BY LINEAR HASH
SYNOPSIS
get_part_id_linear_hash()
part_info A reference to the partition_info struct where all the
desired information is given
no_parts Number of hash partitions
part_expr Item tree of hash function
out:func_value Value of hash function
RETURN VALUE
Calculated partition id
*/
inline
static uint32 get_part_id_linear_hash(partition_info *part_info,
uint no_parts,
Item *part_expr,
longlong *func_value)
{
DBUG_ENTER("get_part_id_linear_hash");
*func_value= part_expr->val_int();
DBUG_RETURN(get_part_id_from_linear_hash(*func_value,
part_info->linear_hash_mask,
no_parts));
}
/*
Calculate part_id for (SUB)PARTITION BY KEY
SYNOPSIS
get_part_id_key()
field_array Array of fields for PARTTION KEY
no_parts Number of KEY partitions
RETURN VALUE
Calculated partition id
*/
inline
static uint32 get_part_id_key(Field **field_array,
uint no_parts,
longlong *func_value)
{
DBUG_ENTER("get_part_id_key");
*func_value= calculate_key_value(field_array);
DBUG_RETURN(*func_value % no_parts);
}
/*
Calculate part_id for (SUB)PARTITION BY LINEAR KEY
SYNOPSIS
get_part_id_linear_key()
part_info A reference to the partition_info struct where all the
desired information is given
field_array Array of fields for PARTTION KEY
no_parts Number of KEY partitions
RETURN VALUE
Calculated partition id
*/
inline
static uint32 get_part_id_linear_key(partition_info *part_info,
Field **field_array,
uint no_parts,
longlong *func_value)
{
DBUG_ENTER("get_partition_id_linear_key");
*func_value= calculate_key_value(field_array);
DBUG_RETURN(get_part_id_from_linear_hash(*func_value,
part_info->linear_hash_mask,
no_parts));
}
/*
This function is used to calculate the partition id where all partition
fields have been prepared to point to a record where the partition field
values are bound.
SYNOPSIS
get_partition_id()
part_info A reference to the partition_info struct where all the
desired information is given
out:part_id The partition id is returned through this pointer
RETURN VALUE
part_id
return TRUE means that the fields of the partition function didn't fit
into any partition and thus the values of the PF-fields are not allowed.
DESCRIPTION
A routine used from write_row, update_row and delete_row from any
handler supporting partitioning. It is also a support routine for
get_partition_set used to find the set of partitions needed to scan
for a certain index scan or full table scan.
It is actually 14 different variants of this function which are called
through a function pointer.
get_partition_id_list
get_partition_id_range
get_partition_id_hash_nosub
get_partition_id_key_nosub
get_partition_id_linear_hash_nosub
get_partition_id_linear_key_nosub
get_partition_id_range_sub_hash
get_partition_id_range_sub_key
get_partition_id_range_sub_linear_hash
get_partition_id_range_sub_linear_key
get_partition_id_list_sub_hash
get_partition_id_list_sub_key
get_partition_id_list_sub_linear_hash
get_partition_id_list_sub_linear_key
*/
/*
This function is used to calculate the main partition to use in the case of
subpartitioning and we don't know enough to get the partition identity in
total.
SYNOPSIS
get_part_partition_id()
part_info A reference to the partition_info struct where all the
desired information is given
out:part_id The partition id is returned through this pointer
RETURN VALUE
part_id
return TRUE means that the fields of the partition function didn't fit
into any partition and thus the values of the PF-fields are not allowed.
DESCRIPTION
It is actually 6 different variants of this function which are called
through a function pointer.
get_partition_id_list
get_partition_id_range
get_partition_id_hash_nosub
get_partition_id_key_nosub
get_partition_id_linear_hash_nosub
get_partition_id_linear_key_nosub
*/
int get_partition_id_list(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
LIST_PART_ENTRY *list_array= part_info->list_array;
int list_index;
longlong list_value;
int min_list_index= 0;
int max_list_index= part_info->no_list_values - 1;
longlong part_func_value= part_info->part_expr->val_int();
DBUG_ENTER("get_partition_id_list");
*func_value= part_func_value;
while (max_list_index >= min_list_index)
{
list_index= (max_list_index + min_list_index) >> 1;
list_value= list_array[list_index].list_value;
if (list_value < part_func_value)
min_list_index= list_index + 1;
else if (list_value > part_func_value)
{
if (!list_index)
goto notfound;
max_list_index= list_index - 1;
}
else
{
*part_id= (uint32)list_array[list_index].partition_id;
DBUG_RETURN(0);
}
}
notfound:
*part_id= 0;
DBUG_RETURN(HA_ERR_NO_PARTITION_FOUND);
}
/*
Find the sub-array part_info->list_array that corresponds to given interval
SYNOPSIS
get_list_array_idx_for_endpoint()
part_info Partitioning info (partitioning type must be LIST)
left_endpoint TRUE - the interval is [a; +inf) or (a; +inf)
FALSE - the interval is (-inf; a] or (-inf; a)
include_endpoint TRUE iff the interval includes the endpoint
DESCRIPTION
This function finds the sub-array of part_info->list_array where values of
list_array[idx].list_value are contained within the specifed interval.
list_array is ordered by list_value, so
1. For [a; +inf) or (a; +inf)-type intervals (left_endpoint==TRUE), the
sought sub-array starts at some index idx and continues till array end.
The function returns first number idx, such that
list_array[idx].list_value is contained within the passed interval.
2. For (-inf; a] or (-inf; a)-type intervals (left_endpoint==FALSE), the
sought sub-array starts at array start and continues till some last
index idx.
The function returns first number idx, such that
list_array[idx].list_value is NOT contained within the passed interval.
If all array elements are contained, part_info->no_list_values is
returned.
NOTE
The caller will call this function and then will run along the sub-array of
list_array to collect partition ids. If the number of list values is
significantly higher then number of partitions, this could be slow and
we could invent some other approach. The "run over list array" part is
already wrapped in a get_next()-like function.
RETURN
The edge of corresponding sub-array of part_info->list_array
*/
uint32 get_list_array_idx_for_endpoint(partition_info *part_info,
bool left_endpoint,
bool include_endpoint)
{
DBUG_ENTER("get_list_array_idx_for_endpoint");
LIST_PART_ENTRY *list_array= part_info->list_array;
uint list_index;
longlong list_value;
uint min_list_index= 0, max_list_index= part_info->no_list_values - 1;
/* Get the partitioning function value for the endpoint */
longlong part_func_value= part_info->part_expr->val_int();
while (max_list_index >= min_list_index)
{
list_index= (max_list_index + min_list_index) >> 1;
list_value= list_array[list_index].list_value;
if (list_value < part_func_value)
min_list_index= list_index + 1;
else if (list_value > part_func_value)
{
if (!list_index)
goto notfound;
max_list_index= list_index - 1;
}
else
{
DBUG_RETURN(list_index + test(left_endpoint ^ include_endpoint));
}
}
notfound:
if (list_value < part_func_value)
list_index++;
DBUG_RETURN(list_index);
}
int get_partition_id_range(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
longlong *range_array= part_info->range_int_array;
uint max_partition= part_info->no_parts - 1;
uint min_part_id= 0;
uint max_part_id= max_partition;
uint loc_part_id;
longlong part_func_value= part_info->part_expr->val_int();
DBUG_ENTER("get_partition_id_int_range");
while (max_part_id > min_part_id)
{
loc_part_id= (max_part_id + min_part_id + 1) >> 1;
if (range_array[loc_part_id] <= part_func_value)
min_part_id= loc_part_id + 1;
else
max_part_id= loc_part_id - 1;
}
loc_part_id= max_part_id;
if (part_func_value >= range_array[loc_part_id])
if (loc_part_id != max_partition)
loc_part_id++;
*part_id= (uint32)loc_part_id;
*func_value= part_func_value;
if (loc_part_id == max_partition)
if (range_array[loc_part_id] != LONGLONG_MAX)
if (part_func_value >= range_array[loc_part_id])
DBUG_RETURN(HA_ERR_NO_PARTITION_FOUND);
DBUG_RETURN(0);
}
/*
Find the sub-array of part_info->range_int_array that covers given interval
SYNOPSIS
get_partition_id_range_for_endpoint()
part_info Partitioning info (partitioning type must be RANGE)
left_endpoint TRUE - the interval is [a; +inf) or (a; +inf)
FALSE - the interval is (-inf; a] or (-inf; a).
include_endpoint TRUE <=> the endpoint itself is included in the
interval
DESCRIPTION
This function finds the sub-array of part_info->range_int_array where the
elements have non-empty intersections with the given interval.
A range_int_array element at index idx represents the interval
[range_int_array[idx-1], range_int_array[idx]),
intervals are disjoint and ordered by their right bound, so
1. For [a; +inf) or (a; +inf)-type intervals (left_endpoint==TRUE), the
sought sub-array starts at some index idx and continues till array end.
The function returns first number idx, such that the interval
represented by range_int_array[idx] has non empty intersection with
the passed interval.
2. For (-inf; a] or (-inf; a)-type intervals (left_endpoint==FALSE), the
sought sub-array starts at array start and continues till some last
index idx.
The function returns first number idx, such that the interval
represented by range_int_array[idx] has EMPTY intersection with the
passed interval.
If the interval represented by the last array element has non-empty
intersection with the passed interval, part_info->no_parts is
returned.
RETURN
The edge of corresponding part_info->range_int_array sub-array.
*/
uint32 get_partition_id_range_for_endpoint(partition_info *part_info,
bool left_endpoint,
bool include_endpoint)
{
DBUG_ENTER("get_partition_id_range_for_endpoint");
longlong *range_array= part_info->range_int_array;
uint max_partition= part_info->no_parts - 1;
uint min_part_id= 0, max_part_id= max_partition, loc_part_id;
/* Get the partitioning function value for the endpoint */
longlong part_func_value= part_info->part_expr->val_int();
while (max_part_id > min_part_id)
{
loc_part_id= (max_part_id + min_part_id + 1) >> 1;
if (range_array[loc_part_id] <= part_func_value)
min_part_id= loc_part_id + 1;
else
max_part_id= loc_part_id - 1;
}
loc_part_id= max_part_id;
if (loc_part_id < max_partition &&
part_func_value >= range_array[loc_part_id+1])
{
loc_part_id++;
}
if (left_endpoint)
{
if (part_func_value >= range_array[loc_part_id])
loc_part_id++;
}
else
{
if (part_func_value == range_array[loc_part_id])
loc_part_id += test(include_endpoint);
else if (part_func_value > range_array[loc_part_id])
loc_part_id++;
loc_part_id++;
}
DBUG_RETURN(loc_part_id);
}
int get_partition_id_hash_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
*part_id= get_part_id_hash(part_info->no_parts, part_info->part_expr,
func_value);
return 0;
}
int get_partition_id_linear_hash_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
*part_id= get_part_id_linear_hash(part_info, part_info->no_parts,
part_info->part_expr, func_value);
return 0;
}
int get_partition_id_key_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
*part_id= get_part_id_key(part_info->part_field_array,
part_info->no_parts, func_value);
return 0;
}
int get_partition_id_linear_key_nosub(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
*part_id= get_part_id_linear_key(part_info,
part_info->part_field_array,
part_info->no_parts, func_value);
return 0;
}
int get_partition_id_range_sub_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_range_sub_hash");
if (unlikely((error= get_partition_id_range(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_hash(no_subparts, part_info->subpart_expr,
&local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
int get_partition_id_range_sub_linear_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_range_sub_linear_hash");
if (unlikely((error= get_partition_id_range(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_linear_hash(part_info, no_subparts,
part_info->subpart_expr,
&local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
int get_partition_id_range_sub_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_range_sub_key");
if (unlikely((error= get_partition_id_range(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_key(part_info->subpart_field_array,
no_subparts, &local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
int get_partition_id_range_sub_linear_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_range_sub_linear_key");
if (unlikely((error= get_partition_id_range(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_linear_key(part_info,
part_info->subpart_field_array,
no_subparts, &local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
int get_partition_id_list_sub_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_list_sub_hash");
if (unlikely((error= get_partition_id_list(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_hash(no_subparts, part_info->subpart_expr,
&local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
int get_partition_id_list_sub_linear_hash(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_list_sub_linear_hash");
if (unlikely((error= get_partition_id_list(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_linear_hash(part_info, no_subparts,
part_info->subpart_expr,
&local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
int get_partition_id_list_sub_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_range_sub_key");
if (unlikely((error= get_partition_id_list(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_key(part_info->subpart_field_array,
no_subparts, &local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
int get_partition_id_list_sub_linear_key(partition_info *part_info,
uint32 *part_id,
longlong *func_value)
{
uint32 loc_part_id, sub_part_id;
uint no_subparts;
longlong local_func_value;
int error;
DBUG_ENTER("get_partition_id_list_sub_linear_key");
if (unlikely((error= get_partition_id_list(part_info, &loc_part_id,
func_value))))
{
DBUG_RETURN(error);
}
no_subparts= part_info->no_subparts;
sub_part_id= get_part_id_linear_key(part_info,
part_info->subpart_field_array,
no_subparts, &local_func_value);
*part_id= get_part_id_for_sub(loc_part_id, sub_part_id, no_subparts);
DBUG_RETURN(0);
}
/*
This function is used to calculate the subpartition id
SYNOPSIS
get_subpartition_id()
part_info A reference to the partition_info struct where all the
desired information is given
RETURN VALUE
part_id The subpartition identity
DESCRIPTION
A routine used in some SELECT's when only partial knowledge of the
partitions is known.
It is actually 4 different variants of this function which are called
through a function pointer.
get_partition_id_hash_sub
get_partition_id_key_sub
get_partition_id_linear_hash_sub
get_partition_id_linear_key_sub
*/
uint32 get_partition_id_hash_sub(partition_info *part_info)
{
longlong func_value;
return get_part_id_hash(part_info->no_subparts, part_info->subpart_expr,
&func_value);
}
uint32 get_partition_id_linear_hash_sub(partition_info *part_info)
{
longlong func_value;
return get_part_id_linear_hash(part_info, part_info->no_subparts,
part_info->subpart_expr, &func_value);
}
uint32 get_partition_id_key_sub(partition_info *part_info)
{
longlong func_value;
return get_part_id_key(part_info->subpart_field_array,
part_info->no_subparts, &func_value);
}
uint32 get_partition_id_linear_key_sub(partition_info *part_info)
{
longlong func_value;
return get_part_id_linear_key(part_info,
part_info->subpart_field_array,
part_info->no_subparts, &func_value);
}
/*
Set an indicator on all partition fields that are set by the key
SYNOPSIS
set_PF_fields_in_key()
key_info Information about the index
key_length Length of key
RETURN VALUE
TRUE Found partition field set by key
FALSE No partition field set by key
*/
static bool set_PF_fields_in_key(KEY *key_info, uint key_length)
{
KEY_PART_INFO *key_part;
bool found_part_field= FALSE;
DBUG_ENTER("set_PF_fields_in_key");
for (key_part= key_info->key_part; (int)key_length > 0; key_part++)
{
if (key_part->null_bit)
key_length--;
if (key_part->type == HA_KEYTYPE_BIT)
{
if (((Field_bit*)key_part->field)->bit_len)
key_length--;
}
if (key_part->key_part_flag & (HA_BLOB_PART + HA_VAR_LENGTH_PART))
{
key_length-= HA_KEY_BLOB_LENGTH;
}
if (key_length < key_part->length)
break;
key_length-= key_part->length;
if (key_part->field->flags & FIELD_IN_PART_FUNC_FLAG)
{
found_part_field= TRUE;
key_part->field->flags|= GET_FIXED_FIELDS_FLAG;
}
}
DBUG_RETURN(found_part_field);
}
/*
We have found that at least one partition field was set by a key, now
check if a partition function has all its fields bound or not.
SYNOPSIS
check_part_func_bound()
ptr Array of fields NULL terminated (partition fields)
RETURN VALUE
TRUE All fields in partition function are set
FALSE Not all fields in partition function are set
*/
static bool check_part_func_bound(Field **ptr)
{
bool result= TRUE;
DBUG_ENTER("check_part_func_bound");
for (; *ptr; ptr++)
{
if (!((*ptr)->flags & GET_FIXED_FIELDS_FLAG))
{
result= FALSE;
break;
}
}
DBUG_RETURN(result);
}
/*
Get the id of the subpartitioning part by using the key buffer of the
index scan.
SYNOPSIS
get_sub_part_id_from_key()
table The table object
buf A buffer that can be used to evaluate the partition function
key_info The index object
key_spec A key_range containing key and key length
RETURN VALUES
part_id Subpartition id to use
DESCRIPTION
Use key buffer to set-up record in buf, move field pointers and
get the partition identity and restore field pointers afterwards.
*/
static uint32 get_sub_part_id_from_key(const TABLE *table,byte *buf,
KEY *key_info,
const key_range *key_spec)
{
byte *rec0= table->record[0];
partition_info *part_info= table->part_info;
uint32 part_id;
DBUG_ENTER("get_sub_part_id_from_key");
key_restore(buf, (byte*)key_spec->key, key_info, key_spec->length);
if (likely(rec0 == buf))
part_id= part_info->get_subpartition_id(part_info);
else
{
Field **part_field_array= part_info->subpart_field_array;
set_field_ptr(part_field_array, buf, rec0);
part_id= part_info->get_subpartition_id(part_info);
set_field_ptr(part_field_array, rec0, buf);
}
DBUG_RETURN(part_id);
}
/*
Get the id of the partitioning part by using the key buffer of the
index scan.
SYNOPSIS
get_part_id_from_key()
table The table object
buf A buffer that can be used to evaluate the partition function
key_info The index object
key_spec A key_range containing key and key length
out:part_id Partition to use
RETURN VALUES
TRUE Partition to use not found
FALSE Ok, part_id indicates partition to use
DESCRIPTION
Use key buffer to set-up record in buf, move field pointers and
get the partition identity and restore field pointers afterwards.
*/
bool get_part_id_from_key(const TABLE *table, byte *buf, KEY *key_info,
const key_range *key_spec, uint32 *part_id)
{
bool result;
byte *rec0= table->record[0];
partition_info *part_info= table->part_info;
longlong func_value;
DBUG_ENTER("get_part_id_from_key");
key_restore(buf, (byte*)key_spec->key, key_info, key_spec->length);
if (likely(rec0 == buf))
result= part_info->get_part_partition_id(part_info, part_id,
&func_value);
else
{
Field **part_field_array= part_info->part_field_array;
set_field_ptr(part_field_array, buf, rec0);
result= part_info->get_part_partition_id(part_info, part_id,
&func_value);
set_field_ptr(part_field_array, rec0, buf);
}
DBUG_RETURN(result);
}
/*
Get the partitioning id of the full PF by using the key buffer of the
index scan.
SYNOPSIS
get_full_part_id_from_key()
table The table object
buf A buffer that is used to evaluate the partition function
key_info The index object
key_spec A key_range containing key and key length
out:part_spec A partition id containing start part and end part
RETURN VALUES
part_spec
No partitions to scan is indicated by end_part > start_part when returning
DESCRIPTION
Use key buffer to set-up record in buf, move field pointers if needed and
get the partition identity and restore field pointers afterwards.
*/
void get_full_part_id_from_key(const TABLE *table, byte *buf,
KEY *key_info,
const key_range *key_spec,
part_id_range *part_spec)
{
bool result;
partition_info *part_info= table->part_info;
byte *rec0= table->record[0];
longlong func_value;
DBUG_ENTER("get_full_part_id_from_key");
key_restore(buf, (byte*)key_spec->key, key_info, key_spec->length);
if (likely(rec0 == buf))
result= part_info->get_partition_id(part_info, &part_spec->start_part,
&func_value);
else
{
Field **part_field_array= part_info->full_part_field_array;
set_field_ptr(part_field_array, buf, rec0);
result= part_info->get_partition_id(part_info, &part_spec->start_part,
&func_value);
set_field_ptr(part_field_array, rec0, buf);
}
part_spec->end_part= part_spec->start_part;
if (unlikely(result))
part_spec->start_part++;
DBUG_VOID_RETURN;
}
/*
Prune the set of partitions to use in query
SYNOPSIS
prune_partition_set()
table The table object
out:part_spec Contains start part, end part
DESCRIPTION
This function is called to prune the range of partitions to scan by
checking the used_partitions bitmap.
If start_part > end_part at return it means no partition needs to be
scanned. If start_part == end_part it always means a single partition
needs to be scanned.
RETURN VALUE
part_spec
*/
void prune_partition_set(const TABLE *table, part_id_range *part_spec)
{
int last_partition= -1;
uint i;
partition_info *part_info= table->part_info;
DBUG_ENTER("prune_partition_set");
for (i= part_spec->start_part; i <= part_spec->end_part; i++)
{
if (bitmap_is_set(&(part_info->used_partitions), i))
{
DBUG_PRINT("info", ("Partition %d is set", i));
if (last_partition == -1)
/* First partition found in set and pruned bitmap */
part_spec->start_part= i;
last_partition= i;
}
}
if (last_partition == -1)
/* No partition found in pruned bitmap */
part_spec->start_part= part_spec->end_part + 1;
else //if (last_partition != -1)
part_spec->end_part= last_partition;
DBUG_VOID_RETURN;
}
/*
Get the set of partitions to use in query.
SYNOPSIS
get_partition_set()
table The table object
buf A buffer that can be used to evaluate the partition function
index The index of the key used, if MAX_KEY no index used
key_spec A key_range containing key and key length
out:part_spec Contains start part, end part and indicator if bitmap is
used for which partitions to scan
DESCRIPTION
This function is called to discover which partitions to use in an index
scan or a full table scan.
It returns a range of partitions to scan. If there are holes in this
range with partitions that are not needed to scan a bit array is used
to signal which partitions to use and which not to use.
If start_part > end_part at return it means no partition needs to be
scanned. If start_part == end_part it always means a single partition
needs to be scanned.
RETURN VALUE
part_spec
*/
void get_partition_set(const TABLE *table, byte *buf, const uint index,
const key_range *key_spec, part_id_range *part_spec)
{
partition_info *part_info= table->part_info;
uint no_parts= part_info->get_tot_partitions();
uint i, part_id;
uint sub_part= no_parts;
uint32 part_part= no_parts;
KEY *key_info= NULL;
bool found_part_field= FALSE;
DBUG_ENTER("get_partition_set");
part_spec->start_part= 0;
part_spec->end_part= no_parts - 1;
if ((index < MAX_KEY) &&
key_spec->flag == (uint)HA_READ_KEY_EXACT &&
part_info->some_fields_in_PF.is_set(index))
{
key_info= table->key_info+index;
/*
The index can potentially provide at least one PF-field (field in the
partition function). Thus it is interesting to continue our probe.
*/
if (key_spec->length == key_info->key_length)
{
/*
The entire key is set so we can check whether we can immediately
derive either the complete PF or if we can derive either
the top PF or the subpartitioning PF. This can be established by
checking precalculated bits on each index.
*/
if (part_info->all_fields_in_PF.is_set(index))
{
/*
We can derive the exact partition to use, no more than this one
is needed.
*/
get_full_part_id_from_key(table,buf,key_info,key_spec,part_spec);
/*
Check if range can be adjusted by looking in used_partitions
*/
prune_partition_set(table, part_spec);
DBUG_VOID_RETURN;
}
else if (part_info->is_sub_partitioned())
{
if (part_info->all_fields_in_SPF.is_set(index))
sub_part= get_sub_part_id_from_key(table, buf, key_info, key_spec);
else if (part_info->all_fields_in_PPF.is_set(index))
{
if (get_part_id_from_key(table,buf,key_info,
key_spec,(uint32*)&part_part))
{
/*
The value of the RANGE or LIST partitioning was outside of
allowed values. Thus it is certain that the result of this
scan will be empty.
*/
part_spec->start_part= no_parts;
DBUG_VOID_RETURN;
}
}
}
}
else
{
/*
Set an indicator on all partition fields that are bound.
If at least one PF-field was bound it pays off to check whether
the PF or PPF or SPF has been bound.
(PF = Partition Function, SPF = Subpartition Function and
PPF = Partition Function part of subpartitioning)
*/
if ((found_part_field= set_PF_fields_in_key(key_info,
key_spec->length)))
{
if (check_part_func_bound(part_info->full_part_field_array))
{
/*
We were able to bind all fields in the partition function even
by using only a part of the key. Calculate the partition to use.
*/
get_full_part_id_from_key(table,buf,key_info,key_spec,part_spec);
clear_indicator_in_key_fields(key_info);
/*
Check if range can be adjusted by looking in used_partitions
*/
prune_partition_set(table, part_spec);
DBUG_VOID_RETURN;
}
else if (part_info->is_sub_partitioned())
{
if (check_part_func_bound(part_info->subpart_field_array))
sub_part= get_sub_part_id_from_key(table, buf, key_info, key_spec);
else if (check_part_func_bound(part_info->part_field_array))
{
if (get_part_id_from_key(table,buf,key_info,key_spec,&part_part))
{
part_spec->start_part= no_parts;
clear_indicator_in_key_fields(key_info);
DBUG_VOID_RETURN;
}
}
}
}
}
}
{
/*
The next step is to analyse the table condition to see whether any
information about which partitions to scan can be derived from there.
Currently not implemented.
*/
}
/*
If we come here we have found a range of sorts we have either discovered
nothing or we have discovered a range of partitions with possible holes
in it. We need a bitvector to further the work here.
*/
if (!(part_part == no_parts && sub_part == no_parts))
{
/*
We can only arrive here if we are using subpartitioning.
*/
if (part_part != no_parts)
{
/*
We know the top partition and need to scan all underlying
subpartitions. This is a range without holes.
*/
DBUG_ASSERT(sub_part == no_parts);
part_spec->start_part= part_part * part_info->no_subparts;
part_spec->end_part= part_spec->start_part+part_info->no_subparts - 1;
}
else
{
DBUG_ASSERT(sub_part != no_parts);
part_spec->start_part= sub_part;
part_spec->end_part=sub_part+
(part_info->no_subparts*(part_info->no_parts-1));
for (i= 0, part_id= sub_part; i < part_info->no_parts;
i++, part_id+= part_info->no_subparts)
; //Set bit part_id in bit array
}
}
if (found_part_field)
clear_indicator_in_key_fields(key_info);
/*
Check if range can be adjusted by looking in used_partitions
*/
prune_partition_set(table, part_spec);
DBUG_VOID_RETURN;
}
/*
If the table is partitioned we will read the partition info into the
.frm file here.
-------------------------------
| Fileinfo 64 bytes |
-------------------------------
| Formnames 7 bytes |
-------------------------------
| Not used 4021 bytes |
-------------------------------
| Keyinfo + record |
-------------------------------
| Padded to next multiple |
| of IO_SIZE |
-------------------------------
| Forminfo 288 bytes |
-------------------------------
| Screen buffer, to make |
|<7C>field names readable |
-------------------------------
| Packed field info |
|<7C>17 + 1 + strlen(field_name) |
| + 1 end of file character |
-------------------------------
| Partition info |
-------------------------------
We provide the length of partition length in Fileinfo[55-58].
Read the partition syntax from the frm file and parse it to get the
data structures of the partitioning.
SYNOPSIS
mysql_unpack_partition()
thd Thread object
part_buf Partition info from frm file
part_info_len Length of partition syntax
table Table object of partitioned table
create_table_ind Is it called from CREATE TABLE
default_db_type What is the default engine of the table
RETURN VALUE
TRUE Error
FALSE Sucess
DESCRIPTION
Read the partition syntax from the current position in the frm file.
Initiate a LEX object, save the list of item tree objects to free after
the query is done. Set-up partition info object such that parser knows
it is called from internally. Call parser to create data structures
(best possible recreation of item trees and so forth since there is no
serialisation of these objects other than in parseable text format).
We need to save the text of the partition functions since it is not
possible to retrace this given an item tree.
*/
bool mysql_unpack_partition(THD *thd, const uchar *part_buf,
uint part_info_len,
uchar *part_state, uint part_state_len,
TABLE* table, bool is_create_table_ind,
handlerton *default_db_type)
{
Item *thd_free_list= thd->free_list;
bool result= TRUE;
partition_info *part_info;
LEX *old_lex= thd->lex;
LEX lex;
DBUG_ENTER("mysql_unpack_partition");
thd->lex= &lex;
lex_start(thd, part_buf, part_info_len);
/*
We need to use the current SELECT_LEX since I need to keep the
Name_resolution_context object which is referenced from the
Item_field objects.
This is not a nice solution since if the parser uses current_select
for anything else it will corrupt the current LEX object.
*/
thd->lex->current_select= old_lex->current_select;
/*
All Items created is put into a free list on the THD object. This list
is used to free all Item objects after completing a query. We don't
want that to happen with the Item tree created as part of the partition
info. This should be attached to the table object and remain so until
the table object is released.
Thus we move away the current list temporarily and start a new list that
we then save in the partition info structure.
*/
thd->free_list= NULL;
lex.part_info= new partition_info();/* Indicates yyparse from this place */
if (!lex.part_info)
{
mem_alloc_error(sizeof(partition_info));
goto end;
}
lex.part_info->part_state= part_state;
lex.part_info->part_state_len= part_state_len;
DBUG_PRINT("info", ("Parse: %s", part_buf));
if (yyparse((void*)thd) || thd->is_fatal_error)
{
free_items(thd->free_list);
goto end;
}
/*
The parsed syntax residing in the frm file can still contain defaults.
The reason is that the frm file is sometimes saved outside of this
MySQL Server and used in backup and restore of clusters or partitioned
tables. It is not certain that the restore will restore exactly the
same default partitioning.
The easiest manner of handling this is to simply continue using the
part_info we already built up during mysql_create_table if we are
in the process of creating a table. If the table already exists we
need to discover the number of partitions for the default parts. Since
the handler object hasn't been created here yet we need to postpone this
to the fix_partition_func method.
*/
DBUG_PRINT("info", ("Successful parse"));
part_info= lex.part_info;
DBUG_PRINT("info", ("default engine = %d, default_db_type = %d",
ha_legacy_type(part_info->default_engine_type),
ha_legacy_type(default_db_type)));
if (is_create_table_ind)
{
if (old_lex->name)
{
/*
This code is executed when we do a CREATE TABLE t1 LIKE t2
old_lex->name contains the t2 and the table we are opening has
name t1.
*/
Table_ident *table_ident= (Table_ident *)old_lex->name;
char *src_db= table_ident->db.str ? table_ident->db.str : thd->db;
char *src_table= table_ident->table.str;
char buf[FN_REFLEN];
build_table_filename(buf, sizeof(buf), src_db, src_table, "");
if (partition_default_handling(table, part_info, buf))
{
result= TRUE;
goto end;
}
}
else
part_info= old_lex->part_info;
}
table->part_info= part_info;
table->file->set_part_info(part_info);
if (part_info->default_engine_type == NULL)
{
part_info->default_engine_type= default_db_type;
}
else
{
DBUG_ASSERT(part_info->default_engine_type == default_db_type);
}
part_info->item_free_list= thd->free_list;
{
/*
This code part allocates memory for the serialised item information for
the partition functions. In most cases this is not needed but if the
table is used for SHOW CREATE TABLES or ALTER TABLE that modifies
partition information it is needed and the info is lost if we don't
save it here so unfortunately we have to do it here even if in most
cases it is not needed. This is a consequence of that item trees are
not serialisable.
*/
uint part_func_len= part_info->part_func_len;
uint subpart_func_len= part_info->subpart_func_len;
char *part_func_string= NULL;
char *subpart_func_string= NULL;
if ((part_func_len &&
!((part_func_string= thd->alloc(part_func_len)))) ||
(subpart_func_len &&
!((subpart_func_string= thd->alloc(subpart_func_len)))))
{
mem_alloc_error(part_func_len);
free_items(thd->free_list);
part_info->item_free_list= 0;
goto end;
}
if (part_func_len)
memcpy(part_func_string, part_info->part_func_string, part_func_len);
if (subpart_func_len)
memcpy(subpart_func_string, part_info->subpart_func_string,
subpart_func_len);
part_info->part_func_string= part_func_string;
part_info->subpart_func_string= subpart_func_string;
}
result= FALSE;
end:
thd->free_list= thd_free_list;
thd->lex= old_lex;
DBUG_RETURN(result);
}
/*
SYNOPSIS
fast_alter_partition_error_handler()
lpt Container for parameters
RETURN VALUES
None
DESCRIPTION
Support routine to clean up after failures of on-line ALTER TABLE
for partition management.
*/
static void fast_alter_partition_error_handler(ALTER_PARTITION_PARAM_TYPE *lpt)
{
DBUG_ENTER("fast_alter_partition_error_handler");
/* TODO: WL 2826 Error handling */
DBUG_VOID_RETURN;
}
/*
SYNOPSIS
fast_end_partition()
thd Thread object
out:copied Number of records copied
out:deleted Number of records deleted
table_list Table list with the one table in it
empty Has nothing been done
lpt Struct to be used by error handler
RETURN VALUES
FALSE Success
TRUE Failure
DESCRIPTION
Support routine to handle the successful cases for partition
management.
*/
static int fast_end_partition(THD *thd, ulonglong copied,
ulonglong deleted,
TABLE_LIST *table_list, bool is_empty,
ALTER_PARTITION_PARAM_TYPE *lpt,
bool written_bin_log)
{
int error;
DBUG_ENTER("fast_end_partition");
thd->proc_info="end";
if (!is_empty)
query_cache_invalidate3(thd, table_list, 0);
error= ha_commit_stmt(thd);
if (ha_commit(thd))
error= 1;
if (!error || is_empty)
{
char tmp_name[80];
if ((!is_empty) && (!written_bin_log) &&
(!thd->lex->no_write_to_binlog))
write_bin_log(thd, FALSE, thd->query, thd->query_length);
close_thread_tables(thd);
my_snprintf(tmp_name, sizeof(tmp_name), ER(ER_INSERT_INFO),
(ulong) (copied + deleted),
(ulong) deleted,
(ulong) 0);
send_ok(thd,copied+deleted,0L,tmp_name);
DBUG_RETURN(FALSE);
}
fast_alter_partition_error_handler(lpt);
DBUG_RETURN(TRUE);
}
/*
Check engine mix that it is correct
SYNOPSIS
check_engine_condition()
p_elem Partition element
default_engine Have user specified engine on table level
inout::engine_type Current engine used
inout::first Is it first partition
RETURN VALUE
TRUE Failed check
FALSE Ok
DESCRIPTION
(specified partition handler ) specified table handler
(NDB, NDB) NDB OK
(MYISAM, MYISAM) - OK
(MYISAM, -) - NOT OK
(MYISAM, -) MYISAM OK
(- , MYISAM) - NOT OK
(- , -) MYISAM OK
(-,-) - OK
(NDB, MYISAM) * NOT OK
*/
static bool check_engine_condition(partition_element *p_elem,
bool default_engine,
handlerton **engine_type,
bool *first)
{
if (*first && default_engine)
*engine_type= p_elem->engine_type;
*first= FALSE;
if ((!default_engine &&
(p_elem->engine_type != *engine_type &&
!p_elem->engine_type)) ||
(default_engine &&
p_elem->engine_type != *engine_type))
return TRUE;
else
return FALSE;
}
/*
We need to check if engine used by all partitions can handle
partitioning natively.
SYNOPSIS
check_native_partitioned()
create_info Create info in CREATE TABLE
out:ret_val Return value
part_info Partition info
thd Thread object
RETURN VALUES
Value returned in bool ret_value
TRUE Native partitioning supported by engine
FALSE Need to use partition handler
Return value from function
TRUE Error
FALSE Success
*/
static bool check_native_partitioned(HA_CREATE_INFO *create_info,bool *ret_val,
partition_info *part_info, THD *thd)
{
List_iterator<partition_element> part_it(part_info->partitions);
bool first= TRUE;
bool default_engine;
handlerton *engine_type= create_info->db_type;
handlerton *old_engine_type= engine_type;
uint i= 0;
handler *file;
uint no_parts= part_info->partitions.elements;
DBUG_ENTER("check_native_partitioned");
default_engine= (create_info->used_fields | HA_CREATE_USED_ENGINE) ?
TRUE : FALSE;
DBUG_PRINT("info", ("engine_type = %u, default = %u",
ha_legacy_type(engine_type),
default_engine));
if (no_parts)
{
do
{
partition_element *part_elem= part_it++;
if (part_info->is_sub_partitioned() &&
part_elem->subpartitions.elements)
{
uint no_subparts= part_elem->subpartitions.elements;
uint j= 0;
List_iterator<partition_element> sub_it(part_elem->subpartitions);
do
{
partition_element *sub_elem= sub_it++;
if (check_engine_condition(sub_elem, default_engine,
&engine_type, &first))
goto error;
} while (++j < no_subparts);
/*
In case of subpartitioning and defaults we allow that only
subparts have specified engines, as long as the parts haven't
specified the wrong engine it's ok.
*/
if (check_engine_condition(part_elem, FALSE,
&engine_type, &first))
goto error;
}
else if (check_engine_condition(part_elem, default_engine,
&engine_type, &first))
goto error;
} while (++i < no_parts);
}
/*
All engines are of the same type. Check if this engine supports
native partitioning.
*/
if (!engine_type)
engine_type= old_engine_type;
DBUG_PRINT("info", ("engine_type = %s",
ha_resolve_storage_engine_name(engine_type)));
if (engine_type->partition_flags &&
(engine_type->partition_flags() & HA_CAN_PARTITION))
{
create_info->db_type= engine_type;
DBUG_PRINT("info", ("Changed to native partitioning"));
*ret_val= TRUE;
}
DBUG_RETURN(FALSE);
error:
/*
Mixed engines not yet supported but when supported it will need
the partition handler
*/
*ret_val= FALSE;
DBUG_RETURN(TRUE);
}
/*
Prepare for ALTER TABLE of partition structure
SYNOPSIS
prep_alter_part_table()
thd Thread object
table Table object
inout:alter_info Alter information
inout:create_info Create info for CREATE TABLE
old_db_type Old engine type
out:partition_changed Boolean indicating whether partition changed
out:fast_alter_partition Boolean indicating whether fast partition
change is requested
RETURN VALUES
TRUE Error
FALSE Success
partition_changed
fast_alter_partition
DESCRIPTION
This method handles all preparations for ALTER TABLE for partitioned
tables
We need to handle both partition management command such as Add Partition
and others here as well as an ALTER TABLE that completely changes the
partitioning and yet others that don't change anything at all. We start
by checking the partition management variants and then check the general
change patterns.
*/
uint prep_alter_part_table(THD *thd, TABLE *table, ALTER_INFO *alter_info,
HA_CREATE_INFO *create_info,
handlerton *old_db_type,
bool *partition_changed,
uint *fast_alter_partition)
{
DBUG_ENTER("prep_alter_part_table");
if (alter_info->flags &
(ALTER_ADD_PARTITION | ALTER_DROP_PARTITION |
ALTER_COALESCE_PARTITION | ALTER_REORGANIZE_PARTITION |
ALTER_TABLE_REORG | ALTER_OPTIMIZE_PARTITION |
ALTER_CHECK_PARTITION | ALTER_ANALYZE_PARTITION |
ALTER_REPAIR_PARTITION | ALTER_REBUILD_PARTITION))
{
partition_info *tab_part_info= table->part_info;
if (!tab_part_info)
{
my_error(ER_PARTITION_MGMT_ON_NONPARTITIONED, MYF(0));
DBUG_RETURN(TRUE);
}
/*
We are going to manipulate the partition info on the table object
so we need to ensure that the data structure of the table object
is freed by setting version to 0. table->s->version= 0 forces a
flush of the table object in close_thread_tables().
*/
uint flags= 0;
table->s->version= 0L;
if (alter_info->flags == ALTER_TABLE_REORG)
{
uint new_part_no, curr_part_no;
ulonglong max_rows= table->s->max_rows;
if (tab_part_info->part_type != HASH_PARTITION ||
tab_part_info->use_default_no_partitions)
{
my_error(ER_REORG_NO_PARAM_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
new_part_no= table->file->get_default_no_partitions(max_rows);
curr_part_no= tab_part_info->no_parts;
if (new_part_no == curr_part_no)
{
/*
No change is needed, we will have the same number of partitions
after the change as before. Thus we can reply ok immediately
without any changes at all.
*/
DBUG_RETURN(fast_end_partition(thd, ULL(0), ULL(0), NULL,
TRUE, NULL, FALSE));
}
else if (new_part_no > curr_part_no)
{
/*
We will add more partitions, we use the ADD PARTITION without
setting the flag for no default number of partitions
*/
alter_info->flags|= ALTER_ADD_PARTITION;
thd->lex->part_info->no_parts= new_part_no - curr_part_no;
}
else
{
/*
We will remove hash partitions, we use the COALESCE PARTITION
without setting the flag for no default number of partitions
*/
alter_info->flags|= ALTER_COALESCE_PARTITION;
alter_info->no_parts= curr_part_no - new_part_no;
}
}
if (table->s->db_type->alter_table_flags &&
(!(flags= table->s->db_type->alter_table_flags(alter_info->flags))))
{
my_error(ER_PARTITION_FUNCTION_FAILURE, MYF(0));
DBUG_RETURN(1);
}
*fast_alter_partition=
((flags & (HA_FAST_CHANGE_PARTITION | HA_PARTITION_ONE_PHASE)) != 0);
DBUG_PRINT("info", ("*fast_alter_partition: %d flags: 0x%x",
*fast_alter_partition, flags));
if (alter_info->flags & ALTER_ADD_PARTITION)
{
/*
We start by moving the new partitions to the list of temporary
partitions. We will then check that the new partitions fit in the
partitioning scheme as currently set-up.
Partitions are always added at the end in ADD PARTITION.
*/
partition_info *alt_part_info= thd->lex->part_info;
uint no_new_partitions= alt_part_info->no_parts;
uint no_orig_partitions= tab_part_info->no_parts;
uint check_total_partitions= no_new_partitions + no_orig_partitions;
uint new_total_partitions= check_total_partitions;
/*
We allow quite a lot of values to be supplied by defaults, however we
must know the number of new partitions in this case.
*/
if (thd->lex->no_write_to_binlog &&
tab_part_info->part_type != HASH_PARTITION)
{
my_error(ER_NO_BINLOG_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
if (no_new_partitions == 0)
{
my_error(ER_ADD_PARTITION_NO_NEW_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
if (tab_part_info->is_sub_partitioned())
{
if (alt_part_info->no_subparts == 0)
alt_part_info->no_subparts= tab_part_info->no_subparts;
else if (alt_part_info->no_subparts != tab_part_info->no_subparts)
{
my_error(ER_ADD_PARTITION_SUBPART_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
check_total_partitions= new_total_partitions*
alt_part_info->no_subparts;
}
if (check_total_partitions > MAX_PARTITIONS)
{
my_error(ER_TOO_MANY_PARTITIONS_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
alt_part_info->part_type= tab_part_info->part_type;
if (alt_part_info->set_up_defaults_for_partitioning(table->file,
ULL(0),
tab_part_info->no_parts))
{
DBUG_RETURN(TRUE);
}
/*
Handling of on-line cases:
ADD PARTITION for RANGE/LIST PARTITIONING:
------------------------------------------
For range and list partitions add partition is simply adding a
new empty partition to the table. If the handler support this we
will use the simple method of doing this. The figure below shows
an example of this and the states involved in making this change.
Existing partitions New added partitions
------ ------ ------ ------ | ------ ------
| | | | | | | | | | | | |
| p0 | | p1 | | p2 | | p3 | | | p4 | | p5 |
------ ------ ------ ------ | ------ ------
PART_NORMAL PART_NORMAL PART_NORMAL PART_NORMAL PART_TO_BE_ADDED*2
PART_NORMAL PART_NORMAL PART_NORMAL PART_NORMAL PART_IS_ADDED*2
The first line is the states before adding the new partitions and the
second line is after the new partitions are added. All the partitions are
in the partitions list, no partitions are placed in the temp_partitions
list.
ADD PARTITION for HASH PARTITIONING
-----------------------------------
This little figure tries to show the various partitions involved when
adding two new partitions to a linear hash based partitioned table with
four partitions to start with, which lists are used and the states they
pass through. Adding partitions to a normal hash based is similar except
that it is always all the existing partitions that are reorganised not
only a subset of them.
Existing partitions New added partitions
------ ------ ------ ------ | ------ ------
| | | | | | | | | | | | |
| p0 | | p1 | | p2 | | p3 | | | p4 | | p5 |
------ ------ ------ ------ | ------ ------
PART_CHANGED PART_CHANGED PART_NORMAL PART_NORMAL PART_TO_BE_ADDED
PART_IS_CHANGED*2 PART_NORMAL PART_NORMAL PART_IS_ADDED
PART_NORMAL PART_NORMAL PART_NORMAL PART_NORMAL PART_IS_ADDED
Reorganised existing partitions
------ ------
| | | |
| p0'| | p1'|
------ ------
p0 - p5 will be in the partitions list of partitions.
p0' and p1' will actually not exist as separate objects, there presence can
be deduced from the state of the partition and also the names of those
partitions can be deduced this way.
After adding the partitions and copying the partition data to p0', p1',
p4 and p5 from p0 and p1 the states change to adapt for the new situation
where p0 and p1 is dropped and replaced by p0' and p1' and the new p4 and
p5 are in the table again.
The first line above shows the states of the partitions before we start
adding and copying partitions, the second after completing the adding
and copying and finally the third line after also dropping the partitions
that are reorganised.
*/
if (*fast_alter_partition &&
tab_part_info->part_type == HASH_PARTITION)
{
uint part_no= 0, start_part= 1, start_sec_part= 1;
uint end_part= 0, end_sec_part= 0;
uint upper_2n= tab_part_info->linear_hash_mask + 1;
uint lower_2n= upper_2n >> 1;
bool all_parts= TRUE;
if (tab_part_info->linear_hash_ind &&
no_new_partitions < upper_2n)
{
/*
An analysis of which parts needs reorganisation shows that it is
divided into two intervals. The first interval is those parts
that are reorganised up until upper_2n - 1. From upper_2n and
onwards it starts again from partition 0 and goes on until
it reaches p(upper_2n - 1). If the last new partition reaches
beyond upper_2n - 1 then the first interval will end with
p(lower_2n - 1) and start with p(no_orig_partitions - lower_2n).
If lower_2n partitions are added then p0 to p(lower_2n - 1) will
be reorganised which means that the two interval becomes one
interval at this point. Thus only when adding less than
lower_2n partitions and going beyond a total of upper_2n we
actually get two intervals.
To exemplify this assume we have 6 partitions to start with and
add 1, 2, 3, 5, 6, 7, 8, 9 partitions.
The first to add after p5 is p6 = 110 in bit numbers. Thus we
can see that 10 = p2 will be partition to reorganise if only one
partition.
If 2 partitions are added we reorganise [p2, p3]. Those two
cases are covered by the second if part below.
If 3 partitions are added we reorganise [p2, p3] U [p0,p0]. This
part is covered by the else part below.
If 5 partitions are added we get [p2,p3] U [p0, p2] = [p0, p3].
This is covered by the first if part where we need the max check
to here use lower_2n - 1.
If 7 partitions are added we get [p2,p3] U [p0, p4] = [p0, p4].
This is covered by the first if part but here we use the first
calculated end_part.
Finally with 9 new partitions we would also reorganise p6 if we
used the method below but we cannot reorganise more partitions
than what we had from the start and thus we simply set all_parts
to TRUE. In this case we don't get into this if-part at all.
*/
all_parts= FALSE;
if (no_new_partitions >= lower_2n)
{
/*
In this case there is only one interval since the two intervals
overlap and this starts from zero to last_part_no - upper_2n
*/
start_part= 0;
end_part= new_total_partitions - (upper_2n + 1);
end_part= max(lower_2n - 1, end_part);
}
else if (new_total_partitions <= upper_2n)
{
/*
Also in this case there is only one interval since we are not
going over a 2**n boundary
*/
start_part= no_orig_partitions - lower_2n;
end_part= start_part + (no_new_partitions - 1);
}
else
{
/* We have two non-overlapping intervals since we are not
passing a 2**n border and we have not at least lower_2n
new parts that would ensure that the intervals become
overlapping.
*/
start_part= no_orig_partitions - lower_2n;
end_part= upper_2n - 1;
start_sec_part= 0;
end_sec_part= new_total_partitions - (upper_2n + 1);
}
}
List_iterator<partition_element> tab_it(tab_part_info->partitions);
part_no= 0;
do
{
partition_element *p_elem= tab_it++;
if (all_parts ||
(part_no >= start_part && part_no <= end_part) ||
(part_no >= start_sec_part && part_no <= end_sec_part))
{
p_elem->part_state= PART_CHANGED;
}
} while (++part_no < no_orig_partitions);
}
/*
Need to concatenate the lists here to make it possible to check the
partition info for correctness using check_partition_info.
For on-line add partition we set the state of this partition to
PART_TO_BE_ADDED to ensure that it is known that it is not yet
usable (becomes usable when partition is created and the switch of
partition configuration is made.
*/
{
List_iterator<partition_element> alt_it(alt_part_info->partitions);
uint part_count= 0;
do
{
partition_element *part_elem= alt_it++;
if (*fast_alter_partition)
part_elem->part_state= PART_TO_BE_ADDED;
if (tab_part_info->partitions.push_back(part_elem))
{
mem_alloc_error(1);
DBUG_RETURN(TRUE);
}
} while (++part_count < no_new_partitions);
tab_part_info->no_parts+= no_new_partitions;
}
/*
If we specify partitions explicitly we don't use defaults anymore.
Using ADD PARTITION also means that we don't have the default number
of partitions anymore. We use this code also for Table reorganisations
and here we don't set any default flags to FALSE.
*/
if (!(alter_info->flags & ALTER_TABLE_REORG))
{
if (!alt_part_info->use_default_partitions)
{
DBUG_PRINT("info", ("part_info= %x", tab_part_info));
tab_part_info->use_default_partitions= FALSE;
}
tab_part_info->use_default_no_partitions= FALSE;
}
}
else if (alter_info->flags == ALTER_DROP_PARTITION)
{
/*
Drop a partition from a range partition and list partitioning is
always safe and can be made more or less immediate. It is necessary
however to ensure that the partition to be removed is safely removed
and that REPAIR TABLE can remove the partition if for some reason the
command to drop the partition failed in the middle.
*/
uint part_count= 0;
uint no_parts_dropped= alter_info->partition_names.elements;
uint no_parts_found= 0;
List_iterator<partition_element> part_it(tab_part_info->partitions);
if (!(tab_part_info->part_type == RANGE_PARTITION ||
tab_part_info->part_type == LIST_PARTITION))
{
my_error(ER_ONLY_ON_RANGE_LIST_PARTITION, MYF(0), "DROP");
DBUG_RETURN(TRUE);
}
if (no_parts_dropped >= tab_part_info->no_parts)
{
my_error(ER_DROP_LAST_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
do
{
partition_element *part_elem= part_it++;
if (is_name_in_list(part_elem->partition_name,
alter_info->partition_names))
{
/*
Set state to indicate that the partition is to be dropped.
*/
no_parts_found++;
part_elem->part_state= PART_TO_BE_DROPPED;
}
} while (++part_count < tab_part_info->no_parts);
if (no_parts_found != no_parts_dropped)
{
my_error(ER_DROP_PARTITION_NON_EXISTENT, MYF(0), "DROP");
DBUG_RETURN(TRUE);
}
if (table->file->is_fk_defined_on_table_or_index(MAX_KEY))
{
my_error(ER_ROW_IS_REFERENCED, MYF(0));
DBUG_RETURN(TRUE);
}
}
else if ((alter_info->flags & ALTER_OPTIMIZE_PARTITION) ||
(alter_info->flags & ALTER_ANALYZE_PARTITION) ||
(alter_info->flags & ALTER_CHECK_PARTITION) ||
(alter_info->flags & ALTER_REPAIR_PARTITION) ||
(alter_info->flags & ALTER_REBUILD_PARTITION))
{
uint no_parts_opt= alter_info->partition_names.elements;
uint part_count= 0;
uint no_parts_found= 0;
List_iterator<partition_element> part_it(tab_part_info->partitions);
do
{
partition_element *part_elem= part_it++;
if ((alter_info->flags & ALTER_ALL_PARTITION) ||
(is_name_in_list(part_elem->partition_name,
alter_info->partition_names)))
{
/*
Mark the partition as a partition to be "changed" by
analyzing/optimizing/rebuilding/checking/repairing
*/
no_parts_found++;
part_elem->part_state= PART_CHANGED;
}
} while (++part_count < tab_part_info->no_parts);
if (no_parts_found != no_parts_opt &&
(!(alter_info->flags & ALTER_ALL_PARTITION)))
{
const char *ptr;
if (alter_info->flags & ALTER_OPTIMIZE_PARTITION)
ptr= "OPTIMIZE";
else if (alter_info->flags & ALTER_ANALYZE_PARTITION)
ptr= "ANALYZE";
else if (alter_info->flags & ALTER_CHECK_PARTITION)
ptr= "CHECK";
else if (alter_info->flags & ALTER_REPAIR_PARTITION)
ptr= "REPAIR";
else
ptr= "REBUILD";
my_error(ER_DROP_PARTITION_NON_EXISTENT, MYF(0), ptr);
DBUG_RETURN(TRUE);
}
}
else if (alter_info->flags & ALTER_COALESCE_PARTITION)
{
uint no_parts_coalesced= alter_info->no_parts;
uint no_parts_remain= tab_part_info->no_parts - no_parts_coalesced;
List_iterator<partition_element> part_it(tab_part_info->partitions);
if (tab_part_info->part_type != HASH_PARTITION)
{
my_error(ER_COALESCE_ONLY_ON_HASH_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
if (no_parts_coalesced == 0)
{
my_error(ER_COALESCE_PARTITION_NO_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
if (no_parts_coalesced >= tab_part_info->no_parts)
{
my_error(ER_DROP_LAST_PARTITION, MYF(0));
DBUG_RETURN(TRUE);
}
/*
Online handling:
COALESCE PARTITION:
-------------------
The figure below shows the manner in which partitions are handled when
performing an on-line coalesce partition and which states they go through
at start, after adding and copying partitions and finally after dropping
the partitions to drop. The figure shows an example using four partitions
to start with, using linear hash and coalescing one partition (always the
last partition).
Using linear hash then all remaining partitions will have a new reorganised
part.
Existing partitions Coalesced partition
------ ------ ------ | ------
| | | | | | | | |
| p0 | | p1 | | p2 | | | p3 |
------ ------ ------ | ------
PART_NORMAL PART_CHANGED PART_NORMAL PART_REORGED_DROPPED
PART_NORMAL PART_IS_CHANGED PART_NORMAL PART_TO_BE_DROPPED
PART_NORMAL PART_NORMAL PART_NORMAL PART_IS_DROPPED
Reorganised existing partitions
------
| |
| p1'|
------
p0 - p3 is in the partitions list.
The p1' partition will actually not be in any list it is deduced from the
state of p1.
*/
{
uint part_count= 0, start_part= 1, start_sec_part= 1;
uint end_part= 0, end_sec_part= 0;
bool all_parts= TRUE;
if (*fast_alter_partition &&
tab_part_info->linear_hash_ind)
{
uint upper_2n= tab_part_info->linear_hash_mask + 1;
uint lower_2n= upper_2n >> 1;
all_parts= FALSE;
if (no_parts_coalesced >= lower_2n)
{
all_parts= TRUE;
}
else if (no_parts_remain >= lower_2n)
{
end_part= tab_part_info->no_parts - (lower_2n + 1);
start_part= no_parts_remain - lower_2n;
}
else
{
start_part= 0;
end_part= tab_part_info->no_parts - (lower_2n + 1);
end_sec_part= (lower_2n >> 1) - 1;
start_sec_part= end_sec_part - (lower_2n - (no_parts_remain + 1));
}
}
do
{
partition_element *p_elem= part_it++;
if (*fast_alter_partition &&
(all_parts ||
(part_count >= start_part && part_count <= end_part) ||
(part_count >= start_sec_part && part_count <= end_sec_part)))
p_elem->part_state= PART_CHANGED;
if (++part_count > no_parts_remain)
{
if (*fast_alter_partition)
p_elem->part_state= PART_REORGED_DROPPED;
else
part_it.remove();
}
} while (part_count < tab_part_info->no_parts);
tab_part_info->no_parts= no_parts_remain;
}
if (!(alter_info->flags & ALTER_TABLE_REORG))
tab_part_info->use_default_no_partitions= FALSE;
}
else if (alter_info->flags == ALTER_REORGANIZE_PARTITION)
{
/*
Reorganise partitions takes a number of partitions that are next
to each other (at least for RANGE PARTITIONS) and then uses those
to create a set of new partitions. So data is copied from those
partitions into the new set of partitions. Those new partitions
can have more values in the LIST value specifications or less both
are allowed. The ranges can be different but since they are
changing a set of consecutive partitions they must cover the same
range as those changed from.
This command can be used on RANGE and LIST partitions.
*/
uint no_parts_reorged= alter_info->partition_names.elements;
uint no_parts_new= thd->lex->part_info->partitions.elements;
partition_info *alt_part_info= thd->lex->part_info;
uint check_total_partitions;
if (no_parts_reorged > tab_part_info->no_parts)
{
my_error(ER_REORG_PARTITION_NOT_EXIST, MYF(0));
DBUG_RETURN(TRUE);
}
if (!(tab_part_info->part_type == RANGE_PARTITION ||
tab_part_info->part_type == LIST_PARTITION) &&
(no_parts_new != no_parts_reorged))
{
my_error(ER_REORG_HASH_ONLY_ON_SAME_NO, MYF(0));
DBUG_RETURN(TRUE);
}
check_total_partitions= tab_part_info->no_parts + no_parts_new;
check_total_partitions-= no_parts_reorged;
if (check_total_partitions > MAX_PARTITIONS)
{
my_error(ER_TOO_MANY_PARTITIONS_ERROR, MYF(0));
DBUG_RETURN(TRUE);
}
/*
Online handling:
REORGANIZE PARTITION:
---------------------
The figure exemplifies the handling of partitions, their state changes and
how they are organised. It exemplifies four partitions where two of the
partitions are reorganised (p1 and p2) into two new partitions (p4 and p5).
The reason of this change could be to change range limits, change list
values or for hash partitions simply reorganise the partition which could
also involve moving them to new disks or new node groups (MySQL Cluster).
Existing partitions
------ ------ ------ ------
| | | | | | | |
| p0 | | p1 | | p2 | | p3 |
------ ------ ------ ------
PART_NORMAL PART_TO_BE_REORGED PART_NORMAL
PART_NORMAL PART_TO_BE_DROPPED PART_NORMAL
PART_NORMAL PART_IS_DROPPED PART_NORMAL
Reorganised new partitions (replacing p1 and p2)
------ ------
| | | |
| p4 | | p5 |
------ ------
PART_TO_BE_ADDED
PART_IS_ADDED
PART_IS_ADDED
All unchanged partitions and the new partitions are in the partitions list
in the order they will have when the change is completed. The reorganised
partitions are placed in the temp_partitions list. PART_IS_ADDED is only a
temporary state not written in the frm file. It is used to ensure we write
the generated partition syntax in a correct manner.
*/
{
List_iterator<partition_element> tab_it(tab_part_info->partitions);
uint part_count= 0;
bool found_first= FALSE;
bool found_last= FALSE;
bool is_last_partition_reorged;
uint drop_count= 0;
longlong tab_max_range= 0, alt_max_range= 0;
do
{
partition_element *part_elem= tab_it++;
is_last_partition_reorged= FALSE;
if (is_name_in_list(part_elem->partition_name,
alter_info->partition_names))
{
is_last_partition_reorged= TRUE;
drop_count++;
tab_max_range= part_elem->range_value;
if (*fast_alter_partition &&
tab_part_info->temp_partitions.push_back(part_elem))
{
mem_alloc_error(1);
DBUG_RETURN(TRUE);
}
if (*fast_alter_partition)
part_elem->part_state= PART_TO_BE_REORGED;
if (!found_first)
{
uint alt_part_count= 0;
found_first= TRUE;
List_iterator<partition_element>
alt_it(alt_part_info->partitions);
do
{
partition_element *alt_part_elem= alt_it++;
alt_max_range= alt_part_elem->range_value;
if (*fast_alter_partition)
alt_part_elem->part_state= PART_TO_BE_ADDED;
if (alt_part_count == 0)
tab_it.replace(alt_part_elem);
else
tab_it.after(alt_part_elem);
} while (++alt_part_count < no_parts_new);
}
else if (found_last)
{
my_error(ER_CONSECUTIVE_REORG_PARTITIONS, MYF(0));
DBUG_RETURN(TRUE);
}
else
tab_it.remove();
}
else
{
if (found_first)
found_last= TRUE;
}
} while (++part_count < tab_part_info->no_parts);
if (drop_count != no_parts_reorged)
{
my_error(ER_DROP_PARTITION_NON_EXISTENT, MYF(0), "REORGANIZE");
DBUG_RETURN(TRUE);
}
if (tab_part_info->part_type == RANGE_PARTITION &&
((is_last_partition_reorged &&
alt_max_range < tab_max_range) ||
(!is_last_partition_reorged &&
alt_max_range != tab_max_range)))
{
/*
For range partitioning the total resulting range before and
after the change must be the same except in one case. This is
when the last partition is reorganised, in this case it is
acceptable to increase the total range.
The reason is that it is not allowed to have "holes" in the
middle of the ranges and thus we should not allow to reorganise
to create "holes". Also we should not allow using REORGANIZE
to drop data.
*/
my_error(ER_REORG_OUTSIDE_RANGE, MYF(0));
DBUG_RETURN(TRUE);
}
tab_part_info->no_parts= check_total_partitions;
}
}
else
{
DBUG_ASSERT(FALSE);
}
*partition_changed= TRUE;
thd->lex->part_info= tab_part_info;
if (alter_info->flags == ALTER_ADD_PARTITION ||
alter_info->flags == ALTER_REORGANIZE_PARTITION)
{
if (check_partition_info(tab_part_info, (handlerton**)NULL,
table->file, ULL(0)))
{
DBUG_RETURN(TRUE);
}
}
}
else
{
/*
When thd->lex->part_info has a reference to a partition_info the
ALTER TABLE contained a definition of a partitioning.
Case I:
If there was a partition before and there is a new one defined.
We use the new partitioning. The new partitioning is already
defined in the correct variable so no work is needed to
accomplish this.
We do however need to update partition_changed to ensure that not
only the frm file is changed in the ALTER TABLE command.
Case IIa:
There was a partitioning before and there is no new one defined.
Also the user has not specified an explicit engine to use.
We use the old partitioning also for the new table. We do this
by assigning the partition_info from the table loaded in
open_ltable to the partition_info struct used by mysql_create_table
later in this method.
Case IIb:
There was a partitioning before and there is no new one defined.
The user has specified an explicit engine to use.
Since the user has specified an explicit engine to use we override
the old partitioning info and create a new table using the specified
engine. This is the reason for the extra check if old and new engine
is equal.
In this case the partition also is changed.
Case III:
There was no partitioning before altering the table, there is
partitioning defined in the altered table. Use the new partitioning.
No work needed since the partitioning info is already in the
correct variable.
In this case we discover one case where the new partitioning is using
the same partition function as the default (PARTITION BY KEY or
PARTITION BY LINEAR KEY with the list of fields equal to the primary
key fields OR PARTITION BY [LINEAR] KEY() for tables without primary
key)
Also here partition has changed and thus a new table must be
created.
Case IV:
There was no partitioning before and no partitioning defined.
Obviously no work needed.
*/
if (table->part_info)
{
if (!thd->lex->part_info &&
create_info->db_type == old_db_type)
thd->lex->part_info= table->part_info;
}
if (thd->lex->part_info)
{
/*
Need to cater for engine types that can handle partition without
using the partition handler.
*/
if (thd->lex->part_info != table->part_info)
*partition_changed= TRUE;
if (create_info->db_type == &partition_hton)
{
if (table->part_info)
{
thd->lex->part_info->default_engine_type=
table->part_info->default_engine_type;
}
else
{
thd->lex->part_info->default_engine_type=
ha_checktype(thd, DB_TYPE_DEFAULT, FALSE, FALSE);
}
}
else
{
bool is_native_partitioned= FALSE;
partition_info *part_info= thd->lex->part_info;
part_info->default_engine_type= create_info->db_type;
if (check_native_partitioned(create_info, &is_native_partitioned,
part_info, thd))
{
DBUG_RETURN(TRUE);
}
if (!is_native_partitioned)
{
DBUG_ASSERT(create_info->db_type != &default_hton);
create_info->db_type= &partition_hton;
}
}
DBUG_PRINT("info", ("default_db_type = %s",
thd->lex->part_info->default_engine_type->name));
}
}
DBUG_RETURN(FALSE);
}
/*
Change partitions, used to implement ALTER TABLE ADD/REORGANIZE/COALESCE
partitions. This method is used to implement both single-phase and multi-
phase implementations of ADD/REORGANIZE/COALESCE partitions.
SYNOPSIS
mysql_change_partitions()
lpt Struct containing parameters
RETURN VALUES
TRUE Failure
FALSE Success
DESCRIPTION
Request handler to add partitions as set in states of the partition
Elements of the lpt parameters used:
create_info Create information used to create partitions
db Database name
table_name Table name
copied Output parameter where number of copied
records are added
deleted Output parameter where number of deleted
records are added
*/
static bool mysql_change_partitions(ALTER_PARTITION_PARAM_TYPE *lpt)
{
char path[FN_REFLEN+1];
DBUG_ENTER("mysql_change_partitions");
build_table_filename(path, sizeof(path), lpt->db, lpt->table_name, "");
DBUG_RETURN(lpt->table->file->change_partitions(lpt->create_info, path,
&lpt->copied,
&lpt->deleted,
lpt->pack_frm_data,
lpt->pack_frm_len));
}
/*
Rename partitions in an ALTER TABLE of partitions
SYNOPSIS
mysql_rename_partitions()
lpt Struct containing parameters
RETURN VALUES
TRUE Failure
FALSE Success
DESCRIPTION
Request handler to rename partitions as set in states of the partition
Parameters used:
db Database name
table_name Table name
*/
static bool mysql_rename_partitions(ALTER_PARTITION_PARAM_TYPE *lpt)
{
char path[FN_REFLEN+1];
DBUG_ENTER("mysql_rename_partitions");
build_table_filename(path, sizeof(path), lpt->db, lpt->table_name, "");
DBUG_RETURN(lpt->table->file->rename_partitions(path));
}
/*
Drop partitions in an ALTER TABLE of partitions
SYNOPSIS
mysql_drop_partitions()
lpt Struct containing parameters
RETURN VALUES
TRUE Failure
FALSE Success
DESCRIPTION
Drop the partitions marked with PART_TO_BE_DROPPED state and remove
those partitions from the list.
Parameters used:
table Table object
db Database name
table_name Table name
*/
static bool mysql_drop_partitions(ALTER_PARTITION_PARAM_TYPE *lpt)
{
char path[FN_REFLEN+1];
partition_info *part_info= lpt->table->part_info;
List_iterator<partition_element> part_it(part_info->partitions);
uint i= 0;
uint remove_count= 0;
DBUG_ENTER("mysql_drop_partitions");
build_table_filename(path, sizeof(path), lpt->db, lpt->table_name, "");
if (lpt->table->file->drop_partitions(path))
{
DBUG_RETURN(TRUE);
}
do
{
partition_element *part_elem= part_it++;
if (part_elem->part_state == PART_IS_DROPPED)
{
part_it.remove();
remove_count++;
}
} while (++i < part_info->no_parts);
part_info->no_parts-= remove_count;
DBUG_RETURN(FALSE);
}
/*
Actually perform the change requested by ALTER TABLE of partitions
previously prepared.
SYNOPSIS
fast_alter_partition_table()
thd Thread object
table Table object
alter_info ALTER TABLE info
create_info Create info for CREATE TABLE
table_list List of the table involved
create_list The fields in the resulting table
key_list The keys in the resulting table
db Database name of new table
table_name Table name of new table
RETURN VALUES
TRUE Error
FALSE Success
DESCRIPTION
Perform all ALTER TABLE operations for partitioned tables that can be
performed fast without a full copy of the original table.
*/
uint fast_alter_partition_table(THD *thd, TABLE *table,
ALTER_INFO *alter_info,
HA_CREATE_INFO *create_info,
TABLE_LIST *table_list,
List<create_field> *create_list,
List<Key> *key_list, const char *db,
const char *table_name,
uint fast_alter_partition)
{
/* Set-up struct used to write frm files */
ulonglong copied= 0;
ulonglong deleted= 0;
partition_info *part_info= table->part_info;
ALTER_PARTITION_PARAM_TYPE lpt_obj;
ALTER_PARTITION_PARAM_TYPE *lpt= &lpt_obj;
bool written_bin_log= TRUE;
DBUG_ENTER("fast_alter_partition_table");
lpt->thd= thd;
lpt->create_info= create_info;
lpt->create_list= create_list;
lpt->key_list= key_list;
lpt->db_options= create_info->table_options;
if (create_info->row_type == ROW_TYPE_DYNAMIC)
lpt->db_options|= HA_OPTION_PACK_RECORD;
lpt->table= table;
lpt->key_info_buffer= 0;
lpt->key_count= 0;
lpt->db= db;
lpt->table_name= table_name;
lpt->copied= 0;
lpt->deleted= 0;
lpt->pack_frm_data= NULL;
lpt->pack_frm_len= 0;
thd->lex->part_info= part_info;
if (alter_info->flags & ALTER_OPTIMIZE_PARTITION ||
alter_info->flags & ALTER_ANALYZE_PARTITION ||
alter_info->flags & ALTER_CHECK_PARTITION ||
alter_info->flags & ALTER_REPAIR_PARTITION)
{
/*
In this case the user has specified that he wants a set of partitions
to be optimised and the partition engine can handle optimising
partitions natively without requiring a full rebuild of the
partitions.
In this case it is enough to call optimise_partitions, there is no
need to change frm files or anything else.
*/
written_bin_log= FALSE;
if (((alter_info->flags & ALTER_OPTIMIZE_PARTITION) &&
(table->file->optimize_partitions(thd))) ||
((alter_info->flags & ALTER_ANALYZE_PARTITION) &&
(table->file->analyze_partitions(thd))) ||
((alter_info->flags & ALTER_CHECK_PARTITION) &&
(table->file->check_partitions(thd))) ||
((alter_info->flags & ALTER_REPAIR_PARTITION) &&
(table->file->repair_partitions(thd))))
{
fast_alter_partition_error_handler(lpt);
DBUG_RETURN(TRUE);
}
}
else if (fast_alter_partition & HA_PARTITION_ONE_PHASE)
{
/*
In the case where the engine supports one phase online partition
changes it is not necessary to have any exclusive locks. The
correctness is upheld instead by transactions being aborted if they
access the table after its partition definition has changed (if they
are still using the old partition definition).
The handler is in this case responsible to ensure that all users
start using the new frm file after it has changed. To implement
one phase it is necessary for the handler to have the master copy
of the frm file and use discovery mechanisms to renew it. Thus
write frm will write the frm, pack the new frm and finally
the frm is deleted and the discovery mechanisms will either restore
back to the old or installing the new after the change is activated.
Thus all open tables will be discovered that they are old, if not
earlier as soon as they try an operation using the old table. One
should ensure that this is checked already when opening a table,
even if it is found in the cache of open tables.
change_partitions will perform all operations and it is the duty of
the handler to ensure that the frm files in the system gets updated
in synch with the changes made and if an error occurs that a proper
error handling is done.
If the MySQL Server crashes at this moment but the handler succeeds
in performing the change then the binlog is not written for the
change. There is no way to solve this as long as the binlog is not
transactional and even then it is hard to solve it completely.
The first approach here was to downgrade locks. Now a different approach
is decided upon. The idea is that the handler will have access to the
ALTER_INFO when store_lock arrives with TL_WRITE_ALLOW_READ. So if the
handler knows that this functionality can be handled with a lower lock
level it will set the lock level to TL_WRITE_ALLOW_WRITE immediately.
Thus the need to downgrade the lock disappears.
1) Write the new frm, pack it and then delete it
2) Perform the change within the handler
*/
if ((mysql_write_frm(lpt, WFRM_INITIAL_WRITE | WFRM_PACK_FRM)) ||
(mysql_change_partitions(lpt)))
{
fast_alter_partition_error_handler(lpt);
DBUG_RETURN(TRUE);
}
}
else if (alter_info->flags == ALTER_DROP_PARTITION)
{
/*
Now after all checks and setting state on dropped partitions we can
start the actual dropping of the partitions.
Drop partition is actually two things happening. The first is that
a lot of records are deleted. The second is that the behaviour of
subsequent updates and writes and deletes will change. The delete
part can be handled without any particular high lock level by
transactional engines whereas non-transactional engines need to
ensure that this change is done with an exclusive lock on the table.
The second part, the change of partitioning does however require
an exclusive lock to install the new partitioning as one atomic
operation. If this is not the case, it is possible for two
transactions to see the change in a different order than their
serialisation order. Thus we need an exclusive lock for both
transactional and non-transactional engines.
For LIST partitions it could be possible to avoid the exclusive lock
(and for RANGE partitions if they didn't rearrange range definitions
after a DROP PARTITION) if one ensured that failed accesses to the
dropped partitions was aborted for sure (thus only possible for
transactional engines).
1) Lock the table in TL_WRITE_ONLY to ensure all other accesses to
the table have completed
2) Write the new frm file where the partitions have changed but are
still remaining with the state PART_TO_BE_DROPPED
3) Write the bin log
4) Prepare MyISAM handlers for drop of partitions
5) Ensure that any users that has opened the table but not yet
reached the abort lock do that before downgrading the lock.
6) Drop the partitions
7) Write the frm file that the partition has been dropped
8) Wait until all accesses using the old frm file has completed
9) Complete query
*/
if ((abort_and_upgrade_lock(lpt)) ||
(mysql_write_frm(lpt, WFRM_INITIAL_WRITE)) ||
((!thd->lex->no_write_to_binlog) &&
(write_bin_log(thd, FALSE,
thd->query, thd->query_length), FALSE)) ||
(table->file->extra(HA_EXTRA_PREPARE_FOR_DELETE)) ||
(close_open_tables_and_downgrade(lpt), FALSE) ||
(mysql_drop_partitions(lpt)) ||
(mysql_write_frm(lpt, WFRM_CREATE_HANDLER_FILES)) ||
(mysql_wait_completed_table(lpt, table), FALSE))
{
fast_alter_partition_error_handler(lpt);
DBUG_RETURN(TRUE);
}
}
else if ((alter_info->flags & ALTER_ADD_PARTITION) &&
(part_info->part_type == RANGE_PARTITION ||
part_info->part_type == LIST_PARTITION))
{
/*
ADD RANGE/LIST PARTITIONS
In this case there are no tuples removed and no tuples are added.
Thus the operation is merely adding a new partition. Thus it is
necessary to perform the change as an atomic operation. Otherwise
someone reading without seeing the new partition could potentially
miss updates made by a transaction serialised before it that are
inserted into the new partition.
1) Write the new frm file where state of added partitions is
changed to PART_TO_BE_ADDED
2) Add the new partitions
3) Lock all partitions in TL_WRITE_ONLY to ensure that no users
are still using the old partitioning scheme. Wait until all
ongoing users have completed before progressing.
4) Write a new frm file of the table where the partitions are added
to the table.
5) Write binlog
6) Wait until all accesses using the old frm file has completed
7) Complete query
*/
if ((mysql_write_frm(lpt, WFRM_INITIAL_WRITE)) ||
(mysql_change_partitions(lpt)) ||
(abort_and_upgrade_lock(lpt)) ||
(mysql_write_frm(lpt, WFRM_CREATE_HANDLER_FILES)) ||
((!thd->lex->no_write_to_binlog) &&
(write_bin_log(thd, FALSE,
thd->query, thd->query_length), FALSE)) ||
(close_open_tables_and_downgrade(lpt), FALSE))
{
fast_alter_partition_error_handler(lpt);
DBUG_RETURN(TRUE);
}
}
else
{
/*
ADD HASH PARTITION/
COALESCE PARTITION/
REBUILD PARTITION/
REORGANIZE PARTITION
In this case all records are still around after the change although
possibly organised into new partitions, thus by ensuring that all
updates go to both the old and the new partitioning scheme we can
actually perform this operation lock-free. The only exception to
this is when REORGANIZE PARTITION adds/drops ranges. In this case
there needs to be an exclusive lock during the time when the range
changes occur.
This is only possible if the handler can ensure double-write for a
period. The double write will ensure that it doesn't matter where the
data is read from since both places are updated for writes. If such
double writing is not performed then it is necessary to perform the
change with the usual exclusive lock. With double writes it is even
possible to perform writes in parallel with the reorganisation of
partitions.
Without double write procedure we get the following procedure.
The only difference with using double write is that we can downgrade
the lock to TL_WRITE_ALLOW_WRITE. Double write in this case only
double writes from old to new. If we had double writing in both
directions we could perform the change completely without exclusive
lock for HASH partitions.
Handlers that perform double writing during the copy phase can actually
use a lower lock level. This can be handled inside store_lock in the
respective handler.
1) Write the new frm file where state of added partitions is
changed to PART_TO_BE_ADDED and the reorganised partitions
are set in state PART_TO_BE_REORGED.
2) Add the new partitions
Copy from the reorganised partitions to the new partitions
3) Lock all partitions in TL_WRITE_ONLY to ensure that no users
are still using the old partitioning scheme. Wait until all
ongoing users have completed before progressing.
4) Prepare MyISAM handlers for rename and delete of partitions
5) Write a new frm file of the table where the partitions are
reorganised.
6) Rename the reorged partitions such that they are no longer
used and rename those added to their real new names.
7) Write bin log
8) Wait until all accesses using the old frm file has completed
9) Drop the reorganised partitions
10)Write a new frm file of the table where the partitions are
reorganised.
11)Wait until all accesses using the old frm file has completed
12)Complete query
*/
if ((mysql_write_frm(lpt, WFRM_INITIAL_WRITE)) ||
(mysql_change_partitions(lpt)) ||
(abort_and_upgrade_lock(lpt)) ||
(mysql_write_frm(lpt, WFRM_CREATE_HANDLER_FILES)) ||
(table->file->extra(HA_EXTRA_PREPARE_FOR_DELETE)) ||
(mysql_rename_partitions(lpt)) ||
((!thd->lex->no_write_to_binlog) &&
(write_bin_log(thd, FALSE,
thd->query, thd->query_length), FALSE)) ||
(close_open_tables_and_downgrade(lpt), FALSE) ||
(mysql_drop_partitions(lpt)) ||
(mysql_write_frm(lpt, 0UL)) ||
(mysql_wait_completed_table(lpt, table), FALSE))
{
fast_alter_partition_error_handler(lpt);
DBUG_RETURN(TRUE);
}
}
/*
A final step is to write the query to the binlog and send ok to the
user
*/
DBUG_RETURN(fast_end_partition(thd, lpt->copied, lpt->deleted,
table_list, FALSE, lpt,
written_bin_log));
}
#endif
/*
Prepare for calling val_int on partition function by setting fields to
point to the record where the values of the PF-fields are stored.
SYNOPSIS
set_field_ptr()
ptr Array of fields to change ptr
new_buf New record pointer
old_buf Old record pointer
DESCRIPTION
Set ptr in field objects of field array to refer to new_buf record
instead of previously old_buf. Used before calling val_int and after
it is used to restore pointers to table->record[0].
This routine is placed outside of partition code since it can be useful
also for other programs.
*/
void set_field_ptr(Field **ptr, const byte *new_buf,
const byte *old_buf)
{
my_ptrdiff_t diff= (new_buf - old_buf);
DBUG_ENTER("set_field_ptr");
do
{
(*ptr)->move_field_offset(diff);
} while (*(++ptr));
DBUG_VOID_RETURN;
}
/*
Prepare for calling val_int on partition function by setting fields to
point to the record where the values of the PF-fields are stored.
This variant works on a key_part reference.
It is not required that all fields are NOT NULL fields.
SYNOPSIS
set_key_field_ptr()
key_info key info with a set of fields to change ptr
new_buf New record pointer
old_buf Old record pointer
DESCRIPTION
Set ptr in field objects of field array to refer to new_buf record
instead of previously old_buf. Used before calling val_int and after
it is used to restore pointers to table->record[0].
This routine is placed outside of partition code since it can be useful
also for other programs.
*/
void set_key_field_ptr(KEY *key_info, const byte *new_buf,
const byte *old_buf)
{
KEY_PART_INFO *key_part= key_info->key_part;
uint key_parts= key_info->key_parts;
uint i= 0;
my_ptrdiff_t diff= (new_buf - old_buf);
DBUG_ENTER("set_key_field_ptr");
do
{
key_part->field->move_field_offset(diff);
key_part++;
} while (++i < key_parts);
DBUG_VOID_RETURN;
}
/*
SYNOPSIS
mem_alloc_error()
size Size of memory attempted to allocate
None
RETURN VALUES
None
DESCRIPTION
A routine to use for all the many places in the code where memory
allocation error can happen, a tremendous amount of them, needs
simple routine that signals this error.
*/
void mem_alloc_error(size_t size)
{
my_error(ER_OUTOFMEMORY, MYF(0), size);
}
#ifdef WITH_PARTITION_STORAGE_ENGINE
/*
Return comma-separated list of used partitions in the provided given string
SYNOPSIS
make_used_partitions_str()
part_info IN Partitioning info
parts_str OUT The string to fill
DESCRIPTION
Generate a list of used partitions (from bits in part_info->used_partitions
bitmap), asd store it into the provided String object.
NOTE
The produced string must not be longer then MAX_PARTITIONS * (1 + FN_LEN).
*/
void make_used_partitions_str(partition_info *part_info, String *parts_str)
{
parts_str->length(0);
partition_element *pe;
uint partition_id= 0;
List_iterator<partition_element> it(part_info->partitions);
if (part_info->is_sub_partitioned())
{
partition_element *head_pe;
while ((head_pe= it++))
{
List_iterator<partition_element> it2(head_pe->subpartitions);
while ((pe= it2++))
{
if (bitmap_is_set(&part_info->used_partitions, partition_id))
{
if (parts_str->length())
parts_str->append(',');
parts_str->append(head_pe->partition_name,
strlen(head_pe->partition_name),
system_charset_info);
parts_str->append('_');
parts_str->append(pe->partition_name,
strlen(pe->partition_name),
system_charset_info);
}
partition_id++;
}
}
}
else
{
while ((pe= it++))
{
if (bitmap_is_set(&part_info->used_partitions, partition_id))
{
if (parts_str->length())
parts_str->append(',');
parts_str->append(pe->partition_name, strlen(pe->partition_name),
system_charset_info);
}
partition_id++;
}
}
}
#endif
/****************************************************************************
* Partition interval analysis support
***************************************************************************/
/*
Setup partition_info::* members related to partitioning range analysis
SYNOPSIS
set_up_partition_func_pointers()
part_info Partitioning info structure
DESCRIPTION
Assuming that passed partition_info structure already has correct values
for members that specify [sub]partitioning type, table fields, and
functions, set up partition_info::* members that are related to
Partitioning Interval Analysis (see get_partitions_in_range_iter for its
definition)
IMPLEMENTATION
There are two available interval analyzer functions:
(1) get_part_iter_for_interval_via_mapping
(2) get_part_iter_for_interval_via_walking
They both have limited applicability:
(1) is applicable for "PARTITION BY <RANGE|LIST>(func(t.field))", where
func is a monotonic function.
(2) is applicable for
"[SUB]PARTITION BY <any-partitioning-type>(any_func(t.integer_field))"
If both are applicable, (1) is preferred over (2).
This function sets part_info::get_part_iter_for_interval according to
this criteria, and also sets some auxilary fields that the function
uses.
*/
#ifdef WITH_PARTITION_STORAGE_ENGINE
static void set_up_range_analysis_info(partition_info *part_info)
{
enum_monotonicity_info minfo;
/* Set the catch-all default */
part_info->get_part_iter_for_interval= NULL;
part_info->get_subpart_iter_for_interval= NULL;
/*
Check if get_part_iter_for_interval_via_mapping() can be used for
partitioning
*/
switch (part_info->part_type) {
case RANGE_PARTITION:
case LIST_PARTITION:
minfo= part_info->part_expr->get_monotonicity_info();
if (minfo != NON_MONOTONIC)
{
part_info->range_analysis_include_bounds=
test(minfo == MONOTONIC_INCREASING);
part_info->get_part_iter_for_interval=
get_part_iter_for_interval_via_mapping;
goto setup_subparts;
}
default:
;
}
/*
Check get_part_iter_for_interval_via_walking() can be used for
partitioning
*/
if (part_info->no_part_fields == 1)
{
Field *field= part_info->part_field_array[0];
switch (field->type()) {
case MYSQL_TYPE_TINY:
case MYSQL_TYPE_SHORT:
case MYSQL_TYPE_LONG:
case MYSQL_TYPE_LONGLONG:
part_info->get_part_iter_for_interval=
get_part_iter_for_interval_via_walking;
break;
default:
;
}
}
setup_subparts:
/*
Check get_part_iter_for_interval_via_walking() can be used for
subpartitioning
*/
if (part_info->no_subpart_fields == 1)
{
Field *field= part_info->subpart_field_array[0];
switch (field->type()) {
case MYSQL_TYPE_TINY:
case MYSQL_TYPE_SHORT:
case MYSQL_TYPE_LONG:
case MYSQL_TYPE_LONGLONG:
part_info->get_subpart_iter_for_interval=
get_part_iter_for_interval_via_walking;
break;
default:
;
}
}
}
typedef uint32 (*get_endpoint_func)(partition_info*, bool left_endpoint,
bool include_endpoint);
/*
Partitioning Interval Analysis: Initialize the iterator for "mapping" case
SYNOPSIS
get_part_iter_for_interval_via_mapping()
part_info Partition info
is_subpart TRUE - act for subpartitioning
FALSE - act for partitioning
min_value minimum field value, in opt_range key format.
max_value minimum field value, in opt_range key format.
flags Some combination of NEAR_MIN, NEAR_MAX, NO_MIN_RANGE,
NO_MAX_RANGE.
part_iter Iterator structure to be initialized
DESCRIPTION
Initialize partition set iterator to walk over the interval in
ordered-array-of-partitions (for RANGE partitioning) or
ordered-array-of-list-constants (for LIST partitioning) space.
IMPLEMENTATION
This function is used when partitioning is done by
<RANGE|LIST>(ascending_func(t.field)), and we can map an interval in
t.field space into a sub-array of partition_info::range_int_array or
partition_info::list_array (see get_partition_id_range_for_endpoint,
get_list_array_idx_for_endpoint for details).
The function performs this interval mapping, and sets the iterator to
traverse the sub-array and return appropriate partitions.
RETURN
0 - No matching partitions (iterator not initialized)
1 - Ok, iterator intialized for traversal of matching partitions.
-1 - All partitions would match (iterator not initialized)
*/
int get_part_iter_for_interval_via_mapping(partition_info *part_info,
bool is_subpart,
char *min_value, char *max_value,
uint flags,
PARTITION_ITERATOR *part_iter)
{
DBUG_ASSERT(!is_subpart);
Field *field= part_info->part_field_array[0];
uint32 max_endpoint_val;
get_endpoint_func get_endpoint;
uint field_len= field->pack_length_in_rec();
if (part_info->part_type == RANGE_PARTITION)
{
get_endpoint= get_partition_id_range_for_endpoint;
max_endpoint_val= part_info->no_parts;
part_iter->get_next= get_next_partition_id_range;
}
else if (part_info->part_type == LIST_PARTITION)
{
get_endpoint= get_list_array_idx_for_endpoint;
max_endpoint_val= part_info->no_list_values;
part_iter->get_next= get_next_partition_id_list;
part_iter->part_info= part_info;
}
else
DBUG_ASSERT(0);
/* Find minimum */
if (flags & NO_MIN_RANGE)
part_iter->part_nums.start= 0;
else
{
/*
Store the interval edge in the record buffer, and call the
function that maps the edge in table-field space to an edge
in ordered-set-of-partitions (for RANGE partitioning) or
index-in-ordered-array-of-list-constants (for LIST) space.
*/
store_key_image_to_rec(field, min_value, field_len);
bool include_endp= part_info->range_analysis_include_bounds ||
!test(flags & NEAR_MIN);
part_iter->part_nums.start= get_endpoint(part_info, 1, include_endp);
if (part_iter->part_nums.start == max_endpoint_val)
return 0; /* No partitions */
}
/* Find maximum, do the same as above but for right interval bound */
if (flags & NO_MAX_RANGE)
part_iter->part_nums.end= max_endpoint_val;
else
{
store_key_image_to_rec(field, max_value, field_len);
bool include_endp= part_info->range_analysis_include_bounds ||
!test(flags & NEAR_MAX);
part_iter->part_nums.end= get_endpoint(part_info, 0, include_endp);
if (part_iter->part_nums.start== part_iter->part_nums.end)
return 0; /* No partitions */
}
return 1; /* Ok, iterator initialized */
}
/* See get_part_iter_for_interval_via_walking for definition of what this is */
#define MAX_RANGE_TO_WALK 10
/*
Partitioning Interval Analysis: Initialize iterator to walk field interval
SYNOPSIS
get_part_iter_for_interval_via_walking()
part_info Partition info
is_subpart TRUE - act for subpartitioning
FALSE - act for partitioning
min_value minimum field value, in opt_range key format.
max_value minimum field value, in opt_range key format.
flags Some combination of NEAR_MIN, NEAR_MAX, NO_MIN_RANGE,
NO_MAX_RANGE.
part_iter Iterator structure to be initialized
DESCRIPTION
Initialize partition set iterator to walk over interval in integer field
space. That is, for "const1 <=? t.field <=? const2" interval, initialize
the iterator to return a set of [sub]partitions obtained with the
following procedure:
get partition id for t.field = const1, return it
get partition id for t.field = const1+1, return it
... t.field = const1+2, ...
... ... ...
... t.field = const2 ...
IMPLEMENTATION
See get_partitions_in_range_iter for general description of interval
analysis. We support walking over the following intervals:
"t.field IS NULL"
"c1 <=? t.field <=? c2", where c1 and c2 are finite.
Intervals with +inf/-inf, and [NULL, c1] interval can be processed but
that is more tricky and I don't have time to do it right now.
Additionally we have these requirements:
* number of values in the interval must be less then number of
[sub]partitions, and
* Number of values in the interval must be less then MAX_RANGE_TO_WALK.
The rationale behind these requirements is that if they are not met
we're likely to hit most of the partitions and traversing the interval
will only add overhead. So it's better return "all partitions used" in
that case.
RETURN
0 - No matching partitions, iterator not initialized
1 - Some partitions would match, iterator intialized for traversing them
-1 - All partitions would match, iterator not initialized
*/
int get_part_iter_for_interval_via_walking(partition_info *part_info,
bool is_subpart,
char *min_value, char *max_value,
uint flags,
PARTITION_ITERATOR *part_iter)
{
Field *field;
uint total_parts;
partition_iter_func get_next_func;
if (is_subpart)
{
field= part_info->subpart_field_array[0];
total_parts= part_info->no_subparts;
get_next_func= get_next_subpartition_via_walking;
}
else
{
field= part_info->part_field_array[0];
total_parts= part_info->no_parts;
get_next_func= get_next_partition_via_walking;
}
/* Handle the "t.field IS NULL" interval, it is a special case */
if (field->real_maybe_null() && !(flags & (NO_MIN_RANGE | NO_MAX_RANGE)) &&
*min_value && *max_value)
{
/*
We don't have a part_iter->get_next() function that would find which
partition "t.field IS NULL" belongs to, so find partition that contains
NULL right here, and return an iterator over singleton set.
*/
uint32 part_id;
field->set_null();
if (is_subpart)
{
part_id= part_info->get_subpartition_id(part_info);
init_single_partition_iterator(part_id, part_iter);
return 1; /* Ok, iterator initialized */
}
else
{
longlong dummy;
if (!part_info->get_partition_id(part_info, &part_id, &dummy))
{
init_single_partition_iterator(part_id, part_iter);
return 1; /* Ok, iterator initialized */
}
}
return 0; /* No partitions match */
}
if (flags & (NO_MIN_RANGE | NO_MAX_RANGE))
return -1; /* Can't handle this interval, have to use all partitions */
/* Get integers for left and right interval bound */
longlong a, b;
uint len= field->pack_length_in_rec();
store_key_image_to_rec(field, min_value, len);
a= field->val_int();
store_key_image_to_rec(field, max_value, len);
b= field->val_int();
a += test(flags & NEAR_MIN);
b += test(!(flags & NEAR_MAX));
uint n_values= b - a;
if (n_values > total_parts || n_values > MAX_RANGE_TO_WALK)
return -1;
part_iter->field_vals.start= a;
part_iter->field_vals.end= b;
part_iter->part_info= part_info;
part_iter->get_next= get_next_func;
return 1;
}
/*
PARTITION_ITERATOR::get_next implementation: enumerate partitions in range
SYNOPSIS
get_next_partition_id_list()
part_iter Partition set iterator structure
DESCRIPTION
This is implementation of PARTITION_ITERATOR::get_next() that returns
[sub]partition ids in [min_partition_id, max_partition_id] range.
RETURN
partition id
NOT_A_PARTITION_ID if there are no more partitions
*/
uint32 get_next_partition_id_range(PARTITION_ITERATOR* part_iter)
{
if (part_iter->part_nums.start== part_iter->part_nums.end)
return NOT_A_PARTITION_ID;
else
return part_iter->part_nums.start++;
}
/*
PARTITION_ITERATOR::get_next implementation for LIST partitioning
SYNOPSIS
get_next_partition_id_list()
part_iter Partition set iterator structure
DESCRIPTION
This implementation of PARTITION_ITERATOR::get_next() is special for
LIST partitioning: it enumerates partition ids in
part_info->list_array[i] where i runs over [min_idx, max_idx] interval.
RETURN
partition id
NOT_A_PARTITION_ID if there are no more partitions
*/
uint32 get_next_partition_id_list(PARTITION_ITERATOR *part_iter)
{
if (part_iter->part_nums.start == part_iter->part_nums.end)
return NOT_A_PARTITION_ID;
else
return part_iter->part_info->list_array[part_iter->
part_nums.start++].partition_id;
}
/*
PARTITION_ITERATOR::get_next implementation: walk over field-space interval
SYNOPSIS
get_next_partition_via_walking()
part_iter Partitioning iterator
DESCRIPTION
This implementation of PARTITION_ITERATOR::get_next() returns ids of
partitions that contain records with partitioning field value within
[start_val, end_val] interval.
RETURN
partition id
NOT_A_PARTITION_ID if there are no more partitioning.
*/
static uint32 get_next_partition_via_walking(PARTITION_ITERATOR *part_iter)
{
uint32 part_id;
Field *field= part_iter->part_info->part_field_array[0];
while (part_iter->field_vals.start != part_iter->field_vals.end)
{
field->store(part_iter->field_vals.start, FALSE);
part_iter->field_vals.start++;
longlong dummy;
if (part_iter->part_info->is_sub_partitioned() &&
!part_iter->part_info->get_part_partition_id(part_iter->part_info,
&part_id, &dummy) ||
!part_iter->part_info->get_partition_id(part_iter->part_info,
&part_id, &dummy))
return part_id;
}
return NOT_A_PARTITION_ID;
}
/* Same as get_next_partition_via_walking, but for subpartitions */
static uint32 get_next_subpartition_via_walking(PARTITION_ITERATOR *part_iter)
{
uint32 part_id;
Field *field= part_iter->part_info->subpart_field_array[0];
if (part_iter->field_vals.start == part_iter->field_vals.end)
return NOT_A_PARTITION_ID;
field->store(part_iter->field_vals.start, FALSE);
part_iter->field_vals.start++;
return part_iter->part_info->get_subpartition_id(part_iter->part_info);
}
#endif
Reference in a new issue View git blame Copy permalink