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mariadb/sql/sql_update.cc
unknown f631b361b6 Table definition cache, part 2 
The table opening process now works the following way:
- Create common TABLE_SHARE object
- Read the .frm file and unpack it into the TABLE_SHARE object
- Create a TABLE object based on the information in the TABLE_SHARE
  object and open a handler to the table object

Other noteworthy changes:
- In TABLE_SHARE the most common strings are now LEX_STRING's
- Better error message when table is not found
- Variable table_cache is now renamed 'table_open_cache'
- New variable 'table_definition_cache' that is the number of table defintions that will be cached
- strxnmov() calls are now fixed to avoid overflows
- strxnmov() will now always add one end \0 to result
- engine objects are now created with a TABLE_SHARE object instead of a TABLE object.
- After creating a field object one must call field->init(table) before using it

- For a busy system this change will give you:
 - Less memory usage for table object
 - Faster opening of tables (if it's has been in use or is in table definition cache)
 - Allow you to cache many table definitions objects
 - Faster drop of table


mysql-test/mysql-test-run.sh:
  Fixed some problems with --gdb option
  Test both with socket and tcp/ip port that all old servers are killed
mysql-test/r/flush_table.result:
  More tests with lock table with 2 threads + flush table
mysql-test/r/information_schema.result:
  Removed old (now wrong) result
mysql-test/r/innodb.result:
  Better error messages (thanks to TDC patch)
mysql-test/r/merge.result:
  Extra flush table test
mysql-test/r/ndb_bitfield.result:
  Better error messages (thanks to TDC patch)
mysql-test/r/ndb_partition_error.result:
  Better error messages (thanks to TDC patch)
mysql-test/r/query_cache.result:
  Remove tables left from old tests
mysql-test/r/temp_table.result:
  Test truncate with temporary tables
mysql-test/r/variables.result:
  Table_cache -> Table_open_cache
mysql-test/t/flush_table.test:
  More tests with lock table with 2 threads + flush table
mysql-test/t/merge.test:
  Extra flush table test
mysql-test/t/multi_update.test:
  Added 'sleep' to make test predictable
mysql-test/t/query_cache.test:
  Remove tables left from old tests
mysql-test/t/temp_table.test:
  Test truncate with temporary tables
mysql-test/t/variables.test:
  Table_cache -> Table_open_cache
mysql-test/valgrind.supp:
  Remove warning that may happens becasue threads dies in different order
mysys/hash.c:
  Fixed wrong DBUG_PRINT
mysys/mf_dirname.c:
  More DBUG
mysys/mf_pack.c:
  Better comment
mysys/mf_tempdir.c:
  More DBUG
  Ensure that we call cleanup_dirname() on all temporary directory paths.
  
  If we don't do this, we will get a failure when comparing temporary table
  names as in some cases the temporary table name is run through convert_dirname())
mysys/my_alloc.c:
  Indentation fix
sql/examples/ha_example.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/examples/ha_example.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/examples/ha_tina.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/examples/ha_tina.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/field.cc:
  Update for table definition cache:
  - Field creation now takes TABLE_SHARE instead of TABLE as argument
    (This is becasue field definitions are now cached in TABLE_SHARE)
    When a field is created, one now must call field->init(TABLE) before using it
  - Use s->db instead of s->table_cache_key
  - Added Field::clone() to create a field in TABLE from a field in TABLE_SHARE
  - make_field() takes TABLE_SHARE as argument instead of TABLE
  - move_field() -> move_field_offset()
sql/field.h:
  Update for table definition cache:
  - Field creation now takes TABLE_SHARE instead of TABLE as argument
    (This is becasue field definitions are now cached in TABLE_SHARE)
    When a field is created, one now must call field->init(TABLE) before using it
  - Added Field::clone() to create a field in TABLE from a field in TABLE_SHARE
  - make_field() takes TABLE_SHARE as argument instead of TABLE
  - move_field() -> move_field_offset()
sql/ha_archive.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_archive.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_berkeley.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Changed name of argument create() to not hide internal 'table' variable.
  table->s  -> table_share
sql/ha_berkeley.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_blackhole.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_blackhole.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_federated.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Fixed comments
  Remove index variable and replace with pointers (simple optimization)
  move_field() -> move_field_offset()
  Removed some strlen() calls
sql/ha_federated.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_heap.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Simplify delete_table() and create() as the given file names are now without extension
sql/ha_heap.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_innodb.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_innodb.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_myisam.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Remove not needed fn_format()
  Fixed for new table->s structure
sql/ha_myisam.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_myisammrg.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Don't set 'is_view' for MERGE tables
  Use new interface to find_temporary_table()
sql/ha_myisammrg.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Added flag HA_NO_COPY_ON_ALTER
sql/ha_ndbcluster.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Fixed wrong calls to strxnmov()
  Give error HA_ERR_TABLE_DEF_CHANGED if table definition has changed
  drop_table -> intern_drop_table()
  table->s -> table_share
  Move part_info to TABLE
  Fixed comments & DBUG print's
  New arguments to print_error()
sql/ha_ndbcluster.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
sql/ha_partition.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  We can't set up or use part_info when creating handler as there is not yet any table object
  New ha_intialise() to work with TDC (Done by Mikael)
sql/ha_partition.h:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  Got set_part_info() from Mikael
sql/handler.cc:
  We new use TABLE_SHARE instead of TABLE when creating engine handlers
  ha_delete_table() now also takes database as an argument
  handler::ha_open() now takes TABLE as argument
  ha_open() now calls ha_allocate_read_write_set()
  Simplify ha_allocate_read_write_set()
  Remove ha_deallocate_read_write_set()
  Use table_share (Cached by table definition cache)
sql/handler.h:
  New table flag: HA_NO_COPY_ON_ALTER (used by merge tables)
  Remove ha_deallocate_read_write_set()
  get_new_handler() now takes TABLE_SHARE as argument
  ha_delete_table() now gets database as argument
sql/item.cc:
  table_name and db are now LEX_STRING objects
  When creating fields, we have now have to call field->init(table)
  move_field -> move_field_offset()
sql/item.h:
  tmp_table_field_from_field_type() now takes an extra paramenter 'fixed_length' to allow one to force usage of CHAR
   instead of BLOB
sql/item_cmpfunc.cc:
  Fixed call to tmp_table_field_from_field_type()
sql/item_create.cc:
  Assert if new not handled cast type
sql/item_func.cc:
  When creating fields, we have now have to call field->init(table)
  dummy_table used by 'sp' now needs a TABLE_SHARE object
sql/item_subselect.cc:
  Trivial code cleanups
sql/item_sum.cc:
  When creating fields, we have now have to call field->init(table)
sql/item_timefunc.cc:
  Item_func_str_to_date::tmp_table_field() now replaced by call to
   tmp_table_field_from_field_type() (see item_timefunc.h)
sql/item_timefunc.h:
  Simply tmp_table_field()
sql/item_uniq.cc:
  When creating fields, we have now have to call field->init(table)
sql/key.cc:
  Added 'KEY' argument to 'find_ref_key' to simplify code
sql/lock.cc:
  More debugging
  Use create_table_def_key() to create key for table cache
  Allocate TABLE_SHARE properly when creating name lock
  Fix that locked_table_name doesn't test same table twice
sql/mysql_priv.h:
  New functions for table definition cache
  New interfaces to a lot of functions.
  New faster interface to find_temporary_table() and close_temporary_table()
sql/mysqld.cc:
  Added support for table definition cache of size 'table_def_size'
  Fixed som calls to strnmov()
  Changed name of 'table_cache' to 'table_open_cache'
sql/opt_range.cc:
  Use new interfaces
  Fixed warnings from valgrind
sql/parse_file.cc:
  Safer calls to strxnmov()
  Fixed typo
sql/set_var.cc:
  Added variable 'table_definition_cache'
  Variable table_cache renamed to 'table_open_cache'
sql/slave.cc:
  Use new interface
sql/sp.cc:
  Proper use of TABLE_SHARE
sql/sp_head.cc:
  Remove compiler warnings
  We have now to call field->init(table)
sql/sp_head.h:
  Pointers to parsed strings are now const
sql/sql_acl.cc:
  table_name is now a LEX_STRING
sql/sql_base.cc:
  Main implementation of table definition cache
  (The #ifdef's are there for the future when table definition cache will replace open table cache)
  Now table definitions are cached indepndent of open tables, which will speed up things when a table is in use at once from several places
  Views are not yet cached; For the moment we only cache if a table is a view or not.
  
  Faster implementation of find_temorary_table()
  Replace 'wait_for_refresh()' with the more general function 'wait_for_condition()'
  Drop table is slightly faster as we can use the table definition cache to know the type of the table
sql/sql_cache.cc:
  table_cache_key and table_name are now LEX_STRING
  'sDBUG print fixes
sql/sql_class.cc:
  table_cache_key is now a LEX_STRING
  safer strxnmov()
sql/sql_class.h:
  Added number of open table shares (table definitions)
sql/sql_db.cc:
  safer strxnmov()
sql/sql_delete.cc:
  Use new interface to find_temporary_table()
sql/sql_derived.cc:
  table_name is now a LEX_STRING
sql/sql_handler.cc:
  TABLE_SHARE->db and TABLE_SHARE->table_name are now LEX_STRING's
sql/sql_insert.cc:
  TABLE_SHARE->db and TABLE_SHARE->table_name are now LEX_STRING's
sql/sql_lex.cc:
  Make parsed string a const (to quickly find out if anything is trying to change the query string)
sql/sql_lex.h:
  Make parsed string a const (to quickly find out if anything is trying to change the query string)
sql/sql_load.cc:
  Safer strxnmov()
sql/sql_parse.cc:
  Better error if wrong DB name
sql/sql_partition.cc:
  part_info moved to TABLE from TABLE_SHARE
  Indentation changes
sql/sql_select.cc:
  Indentation fixes
  Call field->init(TABLE) for new created fields
  Update create_tmp_table() to use TABLE_SHARE properly
sql/sql_select.h:
  Call field->init(TABLE) for new created fields
sql/sql_show.cc:
  table_name is now a LEX_STRING
  part_info moved to TABLE
sql/sql_table.cc:
  Use table definition cache to speed up delete of tables
  Fixed calls to functions with new interfaces
  Don't use 'share_not_to_be_used'
  Instead of doing openfrm() when doing repair, we now have to call
  get_table_share() followed by open_table_from_share().
  Replace some fn_format() with faster unpack_filename().
  Safer strxnmov()
  part_info is now in TABLE
  Added Mikaels patch for partition and ALTER TABLE
  Instead of using 'TABLE_SHARE->is_view' use 'table_flags() & HA_NO_COPY_ON_ALTER
sql/sql_test.cc:
  table_name and table_cache_key are now LEX_STRING's
sql/sql_trigger.cc:
  TABLE_SHARE->db and TABLE_SHARE->table_name are now LEX_STRING's
  safer strxnmov()
  Removed compiler warnings
sql/sql_update.cc:
  Call field->init(TABLE) after field is created
sql/sql_view.cc:
  safer strxnmov()
  Create common TABLE_SHARE object for views to allow us to cache if table is a view
sql/structs.h:
  Added SHOW_TABLE_DEFINITIONS
sql/table.cc:
  Creation and destruct of TABLE_SHARE objects that are common for many TABLE objects
  
  The table opening process now works the following way:
  - Create common TABLE_SHARE object
  - Read the .frm file and unpack it into the TABLE_SHARE object
  - Create a TABLE object based on the information in the TABLE_SHARE
    object and open a handler to the table object
  
  open_table_def() is written in such a way that it should be trival to add parsing of the .frm files in new formats
sql/table.h:
  TABLE objects for the same database table now share a common TABLE_SHARE object
  In TABLE_SHARE the most common strings are now LEX_STRING's
sql/unireg.cc:
  Changed arguments to rea_create_table() to have same order as other functions
  Call field->init(table) for new created fields
sql/unireg.h:
  Added OPEN_VIEW
strings/strxnmov.c:
  Change strxnmov() to always add end \0
  This makes usage of strxnmov() safer as most of MySQL code assumes that strxnmov() will create a null terminated string
2005-11-23 22:45:02 +02:00

1620 lines
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/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult 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 */
/*
Single table and multi table updates of tables.
Multi-table updates were introduced by Sinisa & Monty
*/
#include "mysql_priv.h"
#include "sql_select.h"
#include "sp_head.h"
#include "sql_trigger.h"
static bool safe_update_on_fly(JOIN_TAB *join_tab, List<Item> *fields);
/* Return 0 if row hasn't changed */
static bool compare_record(TABLE *table, query_id_t query_id)
{
if (table->s->blob_fields + table->s->varchar_fields == 0)
return cmp_record(table,record[1]);
/* Compare null bits */
if (memcmp(table->null_flags,
table->null_flags+table->s->rec_buff_length,
table->s->null_bytes))
return TRUE; // Diff in NULL value
/* Compare updated fields */
for (Field **ptr=table->field ; *ptr ; ptr++)
{
if ((*ptr)->query_id == query_id &&
(*ptr)->cmp_binary_offset(table->s->rec_buff_length))
return TRUE;
}
return FALSE;
}
/*
check that all fields are real fields
SYNOPSIS
check_fields()
thd thread handler
items Items for check
RETURN
TRUE Items can't be used in UPDATE
FALSE Items are OK
*/
static bool check_fields(THD *thd, List<Item> &items)
{
List_iterator<Item> it(items);
Item *item;
Item_field *field;
Name_resolution_context *context= &thd->lex->select_lex.context;
while ((item= it++))
{
if (!(field= item->filed_for_view_update()))
{
/* item has name, because it comes from VIEW SELECT list */
my_error(ER_NONUPDATEABLE_COLUMN, MYF(0), item->name);
return TRUE;
}
/*
we make temporary copy of Item_field, to avoid influence of changing
result_field on Item_ref which refer on this field
*/
thd->change_item_tree(it.ref(), new Item_field(thd, field));
}
return FALSE;
}
/*
Process usual UPDATE
SYNOPSIS
mysql_update()
thd thread handler
fields fields for update
values values of fields for update
conds WHERE clause expression
order_num number of elemen in ORDER BY clause
order ORDER BY clause list
limit limit clause
handle_duplicates how to handle duplicates
RETURN
0 - OK
2 - privilege check and openning table passed, but we need to convert to
multi-update because of view substitution
1 - error
*/
int mysql_update(THD *thd,
TABLE_LIST *table_list,
List<Item> &fields,
List<Item> &values,
COND *conds,
uint order_num, ORDER *order,
ha_rows limit,
enum enum_duplicates handle_duplicates, bool ignore)
{
bool using_limit= limit != HA_POS_ERROR;
bool safe_update= thd->options & OPTION_SAFE_UPDATES;
bool used_key_is_modified, transactional_table, will_batch;
int res;
int error, loc_error;
uint used_index= MAX_KEY, dup_key_found;
bool need_sort= TRUE;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
uint want_privilege;
#endif
uint table_count= 0;
query_id_t query_id=thd->query_id, timestamp_query_id;
ha_rows updated, found;
key_map old_used_keys;
TABLE *table;
SQL_SELECT *select;
READ_RECORD info;
SELECT_LEX *select_lex= &thd->lex->select_lex;
bool need_reopen;
DBUG_ENTER("mysql_update");
LINT_INIT(timestamp_query_id);
for ( ; ; )
{
if (open_tables(thd, &table_list, &table_count, 0))
DBUG_RETURN(1);
if (table_list->multitable_view)
{
DBUG_ASSERT(table_list->view != 0);
DBUG_PRINT("info", ("Switch to multi-update"));
/* pass counter value */
thd->lex->table_count= table_count;
/* convert to multiupdate */
DBUG_RETURN(2);
}
if (!lock_tables(thd, table_list, table_count, &need_reopen))
break;
if (!need_reopen)
DBUG_RETURN(1);
close_tables_for_reopen(thd, table_list);
}
if (mysql_handle_derived(thd->lex, &mysql_derived_prepare) ||
(thd->fill_derived_tables() &&
mysql_handle_derived(thd->lex, &mysql_derived_filling)))
DBUG_RETURN(1);
thd->proc_info="init";
table= table_list->table;
table->file->info(HA_STATUS_VARIABLE | HA_STATUS_NO_LOCK);
/* Calculate "table->used_keys" based on the WHERE */
table->used_keys= table->s->keys_in_use;
table->quick_keys.clear_all();
#ifndef NO_EMBEDDED_ACCESS_CHECKS
/* TABLE_LIST contain right privilages request */
want_privilege= table_list->grant.want_privilege;
#endif
if (mysql_prepare_update(thd, table_list, &conds, order_num, order))
DBUG_RETURN(1);
old_used_keys= table->used_keys; // Keys used in WHERE
/*
Change the query_id for the timestamp column so that we can
check if this is modified directly
*/
if (table->timestamp_field)
{
timestamp_query_id=table->timestamp_field->query_id;
table->timestamp_field->query_id=thd->query_id-1;
}
/* Check the fields we are going to modify */
#ifndef NO_EMBEDDED_ACCESS_CHECKS
table_list->grant.want_privilege= table->grant.want_privilege= want_privilege;
table_list->register_want_access(want_privilege);
#endif
/*
Indicate that the set of fields is to be updated by passing 2 for
set_query_id.
*/
if (setup_fields_with_no_wrap(thd, 0, fields, 2, 0, 0))
DBUG_RETURN(1); /* purecov: inspected */
if (table_list->view && check_fields(thd, fields))
{
DBUG_RETURN(1);
}
if (!table_list->updatable || check_key_in_view(thd, table_list))
{
my_error(ER_NON_UPDATABLE_TABLE, MYF(0), table_list->alias, "UPDATE");
DBUG_RETURN(1);
}
if (table->timestamp_field)
{
// Don't set timestamp column if this is modified
if (table->timestamp_field->query_id == thd->query_id)
table->timestamp_field_type= TIMESTAMP_NO_AUTO_SET;
else
{
table->timestamp_field->query_id=timestamp_query_id;
table->file->ha_set_bit_in_write_set(table->timestamp_field->fieldnr);
}
}
#ifndef NO_EMBEDDED_ACCESS_CHECKS
/* Check values */
table_list->grant.want_privilege= table->grant.want_privilege=
(SELECT_ACL & ~table->grant.privilege);
#endif
if (setup_fields(thd, 0, values, 1, 0, 0))
{
free_underlaid_joins(thd, select_lex);
DBUG_RETURN(1); /* purecov: inspected */
}
if (conds)
{
Item::cond_result cond_value;
conds= remove_eq_conds(thd, conds, &cond_value);
if (cond_value == Item::COND_FALSE)
limit= 0; // Impossible WHERE
}
// Don't count on usage of 'only index' when calculating which key to use
table->used_keys.clear_all();
select= make_select(table, 0, 0, conds, 0, &error);
if (error || !limit ||
(select && select->check_quick(thd, safe_update, limit)))
{
delete select;
free_underlaid_joins(thd, select_lex);
if (error)
{
DBUG_RETURN(1); // Error in where
}
send_ok(thd); // No matching records
DBUG_RETURN(0);
}
if (!select && limit != HA_POS_ERROR)
{
if ((used_index= get_index_for_order(table, order, limit)) != MAX_KEY)
need_sort= FALSE;
}
/* If running in safe sql mode, don't allow updates without keys */
if (table->quick_keys.is_clear_all())
{
thd->server_status|=SERVER_QUERY_NO_INDEX_USED;
if (safe_update && !using_limit)
{
my_message(ER_UPDATE_WITHOUT_KEY_IN_SAFE_MODE,
ER(ER_UPDATE_WITHOUT_KEY_IN_SAFE_MODE), MYF(0));
goto err;
}
}
init_ftfuncs(thd, select_lex, 1);
/* Check if we are modifying a key that we are used to search with */
if (select && select->quick)
{
used_index= select->quick->index;
used_key_is_modified= (!select->quick->unique_key_range() &&
select->quick->check_if_keys_used(&fields));
}
else
{
used_key_is_modified= 0;
if (used_index == MAX_KEY) // no index for sort order
used_index= table->file->key_used_on_scan;
if (used_index != MAX_KEY)
used_key_is_modified= check_if_key_used(table, used_index, fields);
}
#ifdef WITH_PARTITION_STORAGE_ENGINE
if (used_key_is_modified || order ||
partition_key_modified(table, fields))
#else
if (used_key_is_modified || order)
#endif
{
/*
We can't update table directly; We must first search after all
matching rows before updating the table!
*/
table->file->ha_retrieve_all_cols();
if (used_index < MAX_KEY && old_used_keys.is_set(used_index))
{
table->key_read=1;
table->file->extra(HA_EXTRA_KEYREAD);
}
/* note: can actually avoid sorting below.. */
if (order && (need_sort || used_key_is_modified))
{
/*
Doing an ORDER BY; Let filesort find and sort the rows we are going
to update
*/
uint length;
SORT_FIELD *sortorder;
ha_rows examined_rows;
used_index= MAX_KEY; // For call to init_read_record()
table->sort.io_cache = (IO_CACHE *) my_malloc(sizeof(IO_CACHE),
MYF(MY_FAE | MY_ZEROFILL));
if (!(sortorder=make_unireg_sortorder(order, &length)) ||
(table->sort.found_records = filesort(thd, table, sortorder, length,
select, limit,
&examined_rows))
== HA_POS_ERROR)
{
free_io_cache(table);
goto err;
}
/*
Filesort has already found and selected the rows we want to update,
so we don't need the where clause
*/
delete select;
select= 0;
}
else
{
/*
We are doing a search on a key that is updated. In this case
we go trough the matching rows, save a pointer to them and
update these in a separate loop based on the pointer.
*/
IO_CACHE tempfile;
if (open_cached_file(&tempfile, mysql_tmpdir,TEMP_PREFIX,
DISK_BUFFER_SIZE, MYF(MY_WME)))
goto err;
/* If quick select is used, initialize it before retrieving rows. */
if (select && select->quick && select->quick->reset())
goto err;
if (used_index == MAX_KEY || (select && select->quick))
init_read_record(&info,thd,table,select,0,1);
else
init_read_record_idx(&info, thd, table, 1, used_index);
thd->proc_info="Searching rows for update";
uint tmp_limit= limit;
while (!(error=info.read_record(&info)) && !thd->killed)
{
if (!(select && select->skip_record()))
{
table->file->position(table->record[0]);
if (my_b_write(&tempfile,table->file->ref,
table->file->ref_length))
{
error=1; /* purecov: inspected */
break; /* purecov: inspected */
}
if (!--limit && using_limit)
{
error= -1;
break;
}
}
else
table->file->unlock_row();
}
if (thd->killed && !error)
error= 1; // Aborted
limit= tmp_limit;
end_read_record(&info);
/* Change select to use tempfile */
if (select)
{
delete select->quick;
if (select->free_cond)
delete select->cond;
select->quick=0;
select->cond=0;
}
else
{
select= new SQL_SELECT;
select->head=table;
}
if (reinit_io_cache(&tempfile,READ_CACHE,0L,0,0))
error=1; /* purecov: inspected */
select->file=tempfile; // Read row ptrs from this file
if (error >= 0)
goto err;
}
if (table->key_read)
{
table->key_read=0;
table->file->extra(HA_EXTRA_NO_KEYREAD);
}
}
if (ignore)
table->file->extra(HA_EXTRA_IGNORE_DUP_KEY);
if (select && select->quick && select->quick->reset())
goto err;
init_read_record(&info,thd,table,select,0,1);
updated= found= 0;
thd->count_cuted_fields= CHECK_FIELD_WARN; /* calc cuted fields */
thd->cuted_fields=0L;
thd->proc_info="Updating";
query_id=thd->query_id;
transactional_table= table->file->has_transactions();
thd->no_trans_update= 0;
thd->abort_on_warning= test(!ignore &&
(thd->variables.sql_mode &
(MODE_STRICT_TRANS_TABLES |
MODE_STRICT_ALL_TABLES)));
will_batch= !table->file->start_bulk_update();
while (!(error=info.read_record(&info)) && !thd->killed)
{
if (!(select && select->skip_record()))
{
store_record(table,record[1]);
if (fill_record_n_invoke_before_triggers(thd, fields, values, 0,
table->triggers,
TRG_EVENT_UPDATE))
break; /* purecov: inspected */
found++;
if (compare_record(table, query_id))
{
if ((res= table_list->view_check_option(thd, ignore)) !=
VIEW_CHECK_OK)
{
found--;
if (res == VIEW_CHECK_SKIP)
continue;
else if (res == VIEW_CHECK_ERROR)
{
error= 1;
break;
}
}
if (will_batch)
{
/*
Typically a batched handler can execute the batched jobs when:
1) When specifically told to do so
2) When it is not a good idea to batch anymore
3) When it is necessary to send batch for other reasons
(One such reason is when READ's must be performed)
1) is covered by exec_bulk_update calls.
2) and 3) is handled by the bulk_update_row method.
bulk_update_row can execute the updates including the one
defined in the bulk_update_row or not including the row
in the call. This is up to the handler implementation and can
vary from call to call.
The dup_key_found reports the number of duplicate keys found
in those updates actually executed. It only reports those if
the extra call with HA_EXTRA_IGNORE_DUP_KEY have been issued.
If this hasn't been issued it returns an error code and can
ignore this number. Thus any handler that implements batching
for UPDATE IGNORE must also handle this extra call properly.
If a duplicate key is found on the record included in this
call then it should be included in the count of dup_key_found
and error should be set to 0 (only if these errors are ignored).
*/
error= table->file->bulk_update_row(table->record[1],
table->record[0],
&dup_key_found);
limit+= dup_key_found;
updated-= dup_key_found;
}
else
{
/* Non-batched update */
error= table->file->update_row((byte*) table->record[1],
(byte*) table->record[0]);
}
if (!error)
{
updated++;
thd->no_trans_update= !transactional_table;
if (table->triggers &&
table->triggers->process_triggers(thd, TRG_EVENT_UPDATE,
TRG_ACTION_AFTER, TRUE))
{
error= 1;
break;
}
}
else if (!ignore || error != HA_ERR_FOUND_DUPP_KEY)
{
thd->fatal_error(); // Force error message
table->file->print_error(error,MYF(0));
error= 1;
break;
}
}
if (!--limit && using_limit)
{
/*
We have reached end-of-file in most common situations where no
batching has occurred and if batching was supposed to occur but
no updates were made and finally when the batch execution was
performed without error and without finding any duplicate keys.
If the batched updates were performed with errors we need to
check and if no error but duplicate key's found we need to
continue since those are not counted for in limit.
*/
if (will_batch &&
((error= table->file->exec_bulk_update(&dup_key_found)) ||
!dup_key_found))
{
if (error)
{
/*
The handler should not report error of duplicate keys if they
are ignored. This is a requirement on batching handlers.
*/
table->file->print_error(error,MYF(0));
error= 1;
break;
}
/*
Either an error was found and we are ignoring errors or there
were duplicate keys found. In both cases we need to correct
the counters and continue the loop.
*/
limit= dup_key_found; //limit is 0 when we get here so need to +
updated-= dup_key_found;
}
else
{
error= -1; // Simulate end of file
break;
}
}
}
else
table->file->unlock_row();
thd->row_count++;
}
dup_key_found= 0;
if (thd->killed && !error)
error= 1; // Aborted
else if (will_batch &&
(loc_error= table->file->exec_bulk_update(&dup_key_found)))
/*
An error has occurred when a batched update was performed and returned
an error indication. It cannot be an allowed duplicate key error since
we require the batching handler to treat this as a normal behavior.
Otherwise we simply remove the number of duplicate keys records found
in the batched update.
*/
{
thd->fatal_error();
table->file->print_error(loc_error,MYF(0));
error= 1;
}
else
updated-= dup_key_found;
if (will_batch)
table->file->end_bulk_update();
end_read_record(&info);
free_io_cache(table); // If ORDER BY
delete select;
thd->proc_info= "end";
VOID(table->file->extra(HA_EXTRA_NO_IGNORE_DUP_KEY));
/*
Invalidate the table in the query cache if something changed.
This must be before binlog writing and ha_autocommit_...
*/
if (updated)
{
query_cache_invalidate3(thd, table_list, 1);
}
/*
error < 0 means really no error at all: we processed all rows until the
last one without error. error > 0 means an error (e.g. unique key
violation and no IGNORE or REPLACE). error == 0 is also an error (if
preparing the record or invoking before triggers fails). See
ha_autocommit_or_rollback(error>=0) and DBUG_RETURN(error>=0) below.
Sometimes we want to binlog even if we updated no rows, in case user used
it to be sure master and slave are in same state.
*/
if ((error < 0) || (updated && !transactional_table))
{
if (mysql_bin_log.is_open())
{
if (error < 0)
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length,
transactional_table, FALSE);
if (mysql_bin_log.write(&qinfo) && transactional_table)
error=1; // Rollback update
}
if (!transactional_table)
thd->options|=OPTION_STATUS_NO_TRANS_UPDATE;
}
if (transactional_table)
{
if (ha_autocommit_or_rollback(thd, error >= 0))
error=1;
}
if (thd->lock)
{
mysql_unlock_tables(thd, thd->lock);
thd->lock=0;
}
free_underlaid_joins(thd, select_lex);
if (error < 0)
{
char buff[STRING_BUFFER_USUAL_SIZE];
sprintf(buff, ER(ER_UPDATE_INFO), (ulong) found, (ulong) updated,
(ulong) thd->cuted_fields);
thd->row_count_func=
(thd->client_capabilities & CLIENT_FOUND_ROWS) ? found : updated;
send_ok(thd, (ulong) thd->row_count_func,
thd->insert_id_used ? thd->insert_id() : 0L,buff);
DBUG_PRINT("info",("%d records updated",updated));
}
thd->count_cuted_fields= CHECK_FIELD_IGNORE; /* calc cuted fields */
thd->abort_on_warning= 0;
free_io_cache(table);
DBUG_RETURN((error >= 0 || thd->net.report_error) ? 1 : 0);
err:
delete select;
free_underlaid_joins(thd, select_lex);
if (table->key_read)
{
table->key_read=0;
table->file->extra(HA_EXTRA_NO_KEYREAD);
}
thd->abort_on_warning= 0;
DBUG_RETURN(1);
}
/*
Prepare items in UPDATE statement
SYNOPSIS
mysql_prepare_update()
thd - thread handler
table_list - global/local table list
conds - conditions
order_num - number of ORDER BY list entries
order - ORDER BY clause list
RETURN VALUE
FALSE OK
TRUE error
*/
bool mysql_prepare_update(THD *thd, TABLE_LIST *table_list,
Item **conds, uint order_num, ORDER *order)
{
TABLE *table= table_list->table;
TABLE_LIST tables;
List<Item> all_fields;
SELECT_LEX *select_lex= &thd->lex->select_lex;
DBUG_ENTER("mysql_prepare_update");
#ifndef NO_EMBEDDED_ACCESS_CHECKS
table_list->grant.want_privilege= table->grant.want_privilege=
(SELECT_ACL & ~table->grant.privilege);
table_list->register_want_access(SELECT_ACL);
#endif
bzero((char*) &tables,sizeof(tables)); // For ORDER BY
tables.table= table;
tables.alias= table_list->alias;
thd->allow_sum_func= 0;
if (setup_tables(thd, &select_lex->context, &select_lex->top_join_list,
table_list, conds, &select_lex->leaf_tables,
FALSE) ||
setup_conds(thd, table_list, select_lex->leaf_tables, conds) ||
select_lex->setup_ref_array(thd, order_num) ||
setup_order(thd, select_lex->ref_pointer_array,
table_list, all_fields, all_fields, order) ||
setup_ftfuncs(select_lex))
DBUG_RETURN(TRUE);
/* Check that we are not using table that we are updating in a sub select */
{
TABLE_LIST *duplicate;
if ((duplicate= unique_table(table_list, table_list->next_global)))
{
update_non_unique_table_error(table_list, "UPDATE", duplicate);
my_error(ER_UPDATE_TABLE_USED, MYF(0), table_list->table_name);
DBUG_RETURN(TRUE);
}
}
select_lex->fix_prepare_information(thd, conds);
DBUG_RETURN(FALSE);
}
/***************************************************************************
Update multiple tables from join
***************************************************************************/
/*
Get table map for list of Item_field
*/
static table_map get_table_map(List<Item> *items)
{
List_iterator_fast<Item> item_it(*items);
Item_field *item;
table_map map= 0;
while ((item= (Item_field *) item_it++))
map|= item->used_tables();
DBUG_PRINT("info",("table_map: 0x%08x", map));
return map;
}
/*
make update specific preparation and checks after opening tables
SYNOPSIS
mysql_multi_update_prepare()
thd thread handler
RETURN
FALSE OK
TRUE Error
*/
bool mysql_multi_update_prepare(THD *thd)
{
LEX *lex= thd->lex;
TABLE_LIST *table_list= lex->query_tables;
TABLE_LIST *tl, *leaves;
List<Item> *fields= &lex->select_lex.item_list;
table_map tables_for_update;
bool update_view= 0;
/*
if this multi-update was converted from usual update, here is table
counter else junk will be assigned here, but then replaced with real
count in open_tables()
*/
uint table_count= lex->table_count;
const bool using_lock_tables= thd->locked_tables != 0;
bool original_multiupdate= (thd->lex->sql_command == SQLCOM_UPDATE_MULTI);
bool need_reopen= FALSE;
DBUG_ENTER("mysql_multi_update_prepare");
/* following need for prepared statements, to run next time multi-update */
thd->lex->sql_command= SQLCOM_UPDATE_MULTI;
reopen_tables:
/* open tables and create derived ones, but do not lock and fill them */
if (((original_multiupdate || need_reopen) &&
open_tables(thd, &table_list, &table_count, 0)) ||
mysql_handle_derived(lex, &mysql_derived_prepare))
DBUG_RETURN(TRUE);
/*
setup_tables() need for VIEWs. JOIN::prepare() will call setup_tables()
second time, but this call will do nothing (there are check for second
call in setup_tables()).
*/
if (setup_tables(thd, &lex->select_lex.context,
&lex->select_lex.top_join_list,
table_list, &lex->select_lex.where,
&lex->select_lex.leaf_tables, FALSE))
DBUG_RETURN(TRUE);
if (setup_fields_with_no_wrap(thd, 0, *fields, 2, 0, 0))
DBUG_RETURN(TRUE);
for (tl= table_list; tl ; tl= tl->next_local)
{
if (tl->view)
{
update_view= 1;
break;
}
}
if (update_view && check_fields(thd, *fields))
{
DBUG_RETURN(TRUE);
}
tables_for_update= get_table_map(fields);
/*
Setup timestamp handling and locking mode
*/
leaves= lex->select_lex.leaf_tables;
for (tl= leaves; tl; tl= tl->next_leaf)
{
TABLE *table= tl->table;
/* Only set timestamp column if this is not modified */
if (table->timestamp_field &&
table->timestamp_field->query_id == thd->query_id)
table->timestamp_field_type= TIMESTAMP_NO_AUTO_SET;
/* if table will be updated then check that it is unique */
if (table->map & tables_for_update)
{
if (!tl->updatable || check_key_in_view(thd, tl))
{
my_error(ER_NON_UPDATABLE_TABLE, MYF(0), tl->alias, "UPDATE");
DBUG_RETURN(TRUE);
}
DBUG_PRINT("info",("setting table `%s` for update", tl->alias));
/*
If table will be updated we should not downgrade lock for it and
leave it as is.
*/
}
else
{
DBUG_PRINT("info",("setting table `%s` for read-only", tl->alias));
/*
If we are using the binary log, we need TL_READ_NO_INSERT to get
correct order of statements. Otherwise, we use a TL_READ lock to
improve performance.
*/
tl->lock_type= using_update_log ? TL_READ_NO_INSERT : TL_READ;
tl->updating= 0;
/* Update TABLE::lock_type accordingly. */
if (!tl->placeholder() && !tl->schema_table && !using_lock_tables)
tl->table->reginfo.lock_type= tl->lock_type;
}
}
for (tl= table_list; tl; tl= tl->next_local)
{
/* Check access privileges for table */
if (!tl->derived)
{
uint want_privilege= tl->updating ? UPDATE_ACL : SELECT_ACL;
if (check_access(thd, want_privilege,
tl->db, &tl->grant.privilege, 0, 0,
test(tl->schema_table)) ||
(grant_option && check_grant(thd, want_privilege, tl, 0, 1, 0)))
DBUG_RETURN(TRUE);
}
}
/* check single table update for view compound from several tables */
for (tl= table_list; tl; tl= tl->next_local)
{
if (tl->effective_algorithm == VIEW_ALGORITHM_MERGE)
{
TABLE_LIST *for_update= 0;
if (tl->check_single_table(&for_update, tables_for_update, tl))
{
my_error(ER_VIEW_MULTIUPDATE, MYF(0),
tl->view_db.str, tl->view_name.str);
DBUG_RETURN(-1);
}
}
}
/* now lock and fill tables */
if (lock_tables(thd, table_list, table_count, &need_reopen))
{
if (!need_reopen)
DBUG_RETURN(TRUE);
/*
We have to reopen tables since some of them were altered or dropped
during lock_tables() or something was done with their triggers.
Let us do some cleanups to be able do setup_table() and setup_fields()
once again.
*/
List_iterator_fast<Item> it(*fields);
Item *item;
while ((item= it++))
item->cleanup();
/* We have to cleanup translation tables of views. */
for (TABLE_LIST *tbl= table_list; tbl; tbl= tbl->next_global)
tbl->cleanup_items();
close_tables_for_reopen(thd, table_list);
goto reopen_tables;
}
/*
Check that we are not using table that we are updating, but we should
skip all tables of UPDATE SELECT itself
*/
lex->select_lex.exclude_from_table_unique_test= TRUE;
/* We only need SELECT privilege for columns in the values list */
for (tl= leaves; tl; tl= tl->next_leaf)
{
TABLE *table= tl->table;
TABLE_LIST *tlist;
if (!(tlist= tl->top_table())->derived)
{
tlist->grant.want_privilege=
(SELECT_ACL & ~tlist->grant.privilege);
table->grant.want_privilege= (SELECT_ACL & ~table->grant.privilege);
}
DBUG_PRINT("info", ("table: %s want_privilege: %u", tl->alias,
(uint) table->grant.want_privilege));
if (tl->lock_type != TL_READ &&
tl->lock_type != TL_READ_NO_INSERT)
{
TABLE_LIST *duplicate;
if ((duplicate= unique_table(tl, table_list)))
{
update_non_unique_table_error(table_list, "UPDATE", duplicate);
DBUG_RETURN(TRUE);
}
}
}
if (thd->fill_derived_tables() &&
mysql_handle_derived(lex, &mysql_derived_filling))
DBUG_RETURN(TRUE);
DBUG_RETURN (FALSE);
}
/*
Setup multi-update handling and call SELECT to do the join
*/
bool mysql_multi_update(THD *thd,
TABLE_LIST *table_list,
List<Item> *fields,
List<Item> *values,
COND *conds,
ulonglong options,
enum enum_duplicates handle_duplicates, bool ignore,
SELECT_LEX_UNIT *unit, SELECT_LEX *select_lex)
{
multi_update *result;
DBUG_ENTER("mysql_multi_update");
if (!(result= new multi_update(table_list,
thd->lex->select_lex.leaf_tables,
fields, values,
handle_duplicates, ignore)))
DBUG_RETURN(TRUE);
thd->no_trans_update= 0;
thd->abort_on_warning= test(thd->variables.sql_mode &
(MODE_STRICT_TRANS_TABLES |
MODE_STRICT_ALL_TABLES));
List<Item> total_list;
(void) mysql_select(thd, &select_lex->ref_pointer_array,
table_list, select_lex->with_wild,
total_list,
conds, 0, (ORDER *) NULL, (ORDER *)NULL, (Item *) NULL,
(ORDER *)NULL,
options | SELECT_NO_JOIN_CACHE | SELECT_NO_UNLOCK |
OPTION_SETUP_TABLES_DONE,
result, unit, select_lex);
delete result;
thd->abort_on_warning= 0;
DBUG_RETURN(FALSE);
}
multi_update::multi_update(TABLE_LIST *table_list,
TABLE_LIST *leaves_list,
List<Item> *field_list, List<Item> *value_list,
enum enum_duplicates handle_duplicates_arg,
bool ignore_arg)
:all_tables(table_list), leaves(leaves_list), update_tables(0),
tmp_tables(0), updated(0), found(0), fields(field_list),
values(value_list), table_count(0), copy_field(0),
handle_duplicates(handle_duplicates_arg), do_update(1), trans_safe(0),
transactional_tables(1), ignore(ignore_arg)
{}
/*
Connect fields with tables and create list of tables that are updated
*/
int multi_update::prepare(List<Item> &not_used_values,
SELECT_LEX_UNIT *lex_unit)
{
TABLE_LIST *table_ref;
SQL_LIST update;
table_map tables_to_update;
Item_field *item;
List_iterator_fast<Item> field_it(*fields);
List_iterator_fast<Item> value_it(*values);
uint i, max_fields;
DBUG_ENTER("multi_update::prepare");
thd->count_cuted_fields= CHECK_FIELD_WARN;
thd->cuted_fields=0L;
thd->proc_info="updating main table";
tables_to_update= get_table_map(fields);
if (!tables_to_update)
{
my_message(ER_NO_TABLES_USED, ER(ER_NO_TABLES_USED), MYF(0));
DBUG_RETURN(1);
}
/*
We have to check values after setup_tables to get used_keys right in
reference tables
*/
if (setup_fields(thd, 0, *values, 1, 0, 0))
DBUG_RETURN(1);
/*
Save tables beeing updated in update_tables
update_table->shared is position for table
Don't use key read on tables that are updated
*/
update.empty();
for (table_ref= leaves; table_ref; table_ref= table_ref->next_leaf)
{
/* TODO: add support of view of join support */
TABLE *table=table_ref->table;
if (tables_to_update & table->map)
{
TABLE_LIST *tl= (TABLE_LIST*) thd->memdup((char*) table_ref,
sizeof(*tl));
if (!tl)
DBUG_RETURN(1);
update.link_in_list((byte*) tl, (byte**) &tl->next_local);
tl->shared= table_count++;
table->no_keyread=1;
table->used_keys.clear_all();
table->pos_in_table_list= tl;
}
}
table_count= update.elements;
update_tables= (TABLE_LIST*) update.first;
tmp_tables = (TABLE**) thd->calloc(sizeof(TABLE *) * table_count);
tmp_table_param = (TMP_TABLE_PARAM*) thd->calloc(sizeof(TMP_TABLE_PARAM) *
table_count);
fields_for_table= (List_item **) thd->alloc(sizeof(List_item *) *
table_count);
values_for_table= (List_item **) thd->alloc(sizeof(List_item *) *
table_count);
if (thd->is_fatal_error)
DBUG_RETURN(1);
for (i=0 ; i < table_count ; i++)
{
fields_for_table[i]= new List_item;
values_for_table[i]= new List_item;
}
if (thd->is_fatal_error)
DBUG_RETURN(1);
/* Split fields into fields_for_table[] and values_by_table[] */
while ((item= (Item_field *) field_it++))
{
Item *value= value_it++;
uint offset= item->field->table->pos_in_table_list->shared;
fields_for_table[offset]->push_back(item);
values_for_table[offset]->push_back(value);
}
if (thd->is_fatal_error)
DBUG_RETURN(1);
/* Allocate copy fields */
max_fields=0;
for (i=0 ; i < table_count ; i++)
set_if_bigger(max_fields, fields_for_table[i]->elements);
copy_field= new Copy_field[max_fields];
/*
Mark all copies of tables that are updates to ensure that
init_read_record() will not try to enable a cache on them
The problem is that for queries like
UPDATE t1, t1 AS t2 SET t1.b=t2.c WHERE t1.a=t2.a;
the row buffer may contain things that doesn't match what is on disk
which will cause an error when reading a row.
(This issue is mostly relevent for MyISAM tables)
*/
for (table_ref= leaves; table_ref; table_ref= table_ref->next_leaf)
{
TABLE *table=table_ref->table;
if (!(tables_to_update & table->map) &&
find_table_in_local_list(update_tables, table_ref->db,
table_ref->table_name))
table->no_cache= 1; // Disable row cache
}
DBUG_RETURN(thd->is_fatal_error != 0);
}
/*
Initialize table for multi table
IMPLEMENTATION
- Update first table in join on the fly, if possible
- Create temporary tables to store changed values for all other tables
that are updated (and main_table if the above doesn't hold).
*/
bool
multi_update::initialize_tables(JOIN *join)
{
TABLE_LIST *table_ref;
DBUG_ENTER("initialize_tables");
if ((thd->options & OPTION_SAFE_UPDATES) && error_if_full_join(join))
DBUG_RETURN(1);
main_table=join->join_tab->table;
trans_safe= transactional_tables= main_table->file->has_transactions();
table_to_update= 0;
/* Create a temporary table for keys to all tables, except main table */
for (table_ref= update_tables; table_ref; table_ref= table_ref->next_local)
{
TABLE *table=table_ref->table;
uint cnt= table_ref->shared;
Item_field *ifield;
List<Item> temp_fields= *fields_for_table[cnt];
ORDER group;
if (table == main_table) // First table in join
{
if (safe_update_on_fly(join->join_tab, &temp_fields))
{
table_to_update= main_table; // Update table on the fly
continue;
}
}
TMP_TABLE_PARAM *tmp_param= tmp_table_param+cnt;
/*
Create a temporary table to store all fields that are changed for this
table. The first field in the temporary table is a pointer to the
original row so that we can find and update it
*/
/* ok to be on stack as this is not referenced outside of this func */
Field_string offset(table->file->ref_length, 0, "offset",
&my_charset_bin);
offset.init(table);
if (!(ifield= new Item_field(((Field *) &offset))))
DBUG_RETURN(1);
ifield->maybe_null= 0;
if (temp_fields.push_front(ifield))
DBUG_RETURN(1);
/* Make an unique key over the first field to avoid duplicated updates */
bzero((char*) &group, sizeof(group));
group.asc= 1;
group.item= (Item**) temp_fields.head_ref();
tmp_param->quick_group=1;
tmp_param->field_count=temp_fields.elements;
tmp_param->group_parts=1;
tmp_param->group_length= table->file->ref_length;
if (!(tmp_tables[cnt]=create_tmp_table(thd,
tmp_param,
temp_fields,
(ORDER*) &group, 0, 0,
TMP_TABLE_ALL_COLUMNS,
HA_POS_ERROR,
(char *) "")))
DBUG_RETURN(1);
tmp_tables[cnt]->file->extra(HA_EXTRA_WRITE_CACHE);
}
DBUG_RETURN(0);
}
/*
Check if table is safe to update on fly
SYNOPSIS
safe_update_on_fly
join_tab How table is used in join
fields Fields that are updated
NOTES
We can update the first table in join on the fly if we know that
a row in this table will never be read twice. This is true under
the following conditions:
- We are doing a table scan and the data is in a separate file (MyISAM) or
if we don't update a clustered key.
- We are doing a range scan and we don't update the scan key or
the primary key for a clustered table handler.
When checking for above cases we also should take into account that
BEFORE UPDATE trigger potentially may change value of any field in row
being updated.
WARNING
This code is a bit dependent of how make_join_readinfo() works.
RETURN
0 Not safe to update
1 Safe to update
*/
static bool safe_update_on_fly(JOIN_TAB *join_tab, List<Item> *fields)
{
TABLE *table= join_tab->table;
switch (join_tab->type) {
case JT_SYSTEM:
case JT_CONST:
case JT_EQ_REF:
return TRUE; // At most one matching row
case JT_REF:
case JT_REF_OR_NULL:
return !check_if_key_used(table, join_tab->ref.key, *fields) &&
!(table->triggers &&
table->triggers->has_before_update_triggers());
case JT_ALL:
/* If range search on index */
if (join_tab->quick)
return !join_tab->quick->check_if_keys_used(fields) &&
!(table->triggers &&
table->triggers->has_before_update_triggers());
/* If scanning in clustered key */
if ((table->file->table_flags() & HA_PRIMARY_KEY_IN_READ_INDEX) &&
table->s->primary_key < MAX_KEY)
return !check_if_key_used(table, table->s->primary_key, *fields) &&
!(table->triggers &&
table->triggers->has_before_update_triggers());
return TRUE;
default:
break; // Avoid compler warning
}
return FALSE;
}
multi_update::~multi_update()
{
TABLE_LIST *table;
for (table= update_tables ; table; table= table->next_local)
table->table->no_keyread= table->table->no_cache= 0;
if (tmp_tables)
{
for (uint cnt = 0; cnt < table_count; cnt++)
{
if (tmp_tables[cnt])
{
free_tmp_table(thd, tmp_tables[cnt]);
tmp_table_param[cnt].cleanup();
}
}
}
if (copy_field)
delete [] copy_field;
thd->count_cuted_fields= CHECK_FIELD_IGNORE; // Restore this setting
if (!trans_safe)
thd->options|=OPTION_STATUS_NO_TRANS_UPDATE;
}
bool multi_update::send_data(List<Item> &not_used_values)
{
TABLE_LIST *cur_table;
DBUG_ENTER("multi_update::send_data");
for (cur_table= update_tables; cur_table; cur_table= cur_table->next_local)
{
TABLE *table= cur_table->table;
/*
Check if we are using outer join and we didn't find the row
or if we have already updated this row in the previous call to this
function.
The same row may be presented here several times in a join of type
UPDATE t1 FROM t1,t2 SET t1.a=t2.a
In this case we will do the update for the first found row combination.
The join algorithm guarantees that we will not find the a row in
t1 several times.
*/
if (table->status & (STATUS_NULL_ROW | STATUS_UPDATED))
continue;
uint offset= cur_table->shared;
table->file->position(table->record[0]);
if (table == table_to_update)
{
table->status|= STATUS_UPDATED;
store_record(table,record[1]);
if (fill_record_n_invoke_before_triggers(thd, *fields_for_table[offset],
*values_for_table[offset], 0,
table->triggers,
TRG_EVENT_UPDATE))
DBUG_RETURN(1);
found++;
if (compare_record(table, thd->query_id))
{
int error;
if ((error= cur_table->view_check_option(thd, ignore)) !=
VIEW_CHECK_OK)
{
found--;
if (error == VIEW_CHECK_SKIP)
continue;
else if (error == VIEW_CHECK_ERROR)
DBUG_RETURN(1);
}
if (!updated++)
{
/*
Inform the main table that we are going to update the table even
while we may be scanning it. This will flush the read cache
if it's used.
*/
main_table->file->extra(HA_EXTRA_PREPARE_FOR_UPDATE);
}
if ((error=table->file->update_row(table->record[1],
table->record[0])))
{
updated--;
if (!ignore || error != HA_ERR_FOUND_DUPP_KEY)
{
thd->fatal_error(); // Force error message
table->file->print_error(error,MYF(0));
DBUG_RETURN(1);
}
}
else
{
if (!table->file->has_transactions())
thd->no_trans_update= 1;
if (table->triggers &&
table->triggers->process_triggers(thd, TRG_EVENT_UPDATE,
TRG_ACTION_AFTER, TRUE))
DBUG_RETURN(1);
}
}
}
else
{
int error;
TABLE *tmp_table= tmp_tables[offset];
fill_record(thd, tmp_table->field+1, *values_for_table[offset], 1);
found++;
/* Store pointer to row */
memcpy((char*) tmp_table->field[0]->ptr,
(char*) table->file->ref, table->file->ref_length);
/* Write row, ignoring duplicated updates to a row */
if ((error= tmp_table->file->write_row(tmp_table->record[0])) &&
(error != HA_ERR_FOUND_DUPP_KEY &&
error != HA_ERR_FOUND_DUPP_UNIQUE))
{
if (create_myisam_from_heap(thd, tmp_table, tmp_table_param + offset,
error, 1))
{
do_update=0;
DBUG_RETURN(1); // Not a table_is_full error
}
}
}
}
DBUG_RETURN(0);
}
void multi_update::send_error(uint errcode,const char *err)
{
/* First send error what ever it is ... */
my_error(errcode, MYF(0), err);
/* If nothing updated return */
if (!updated)
return;
/* Something already updated so we have to invalidate cache */
query_cache_invalidate3(thd, update_tables, 1);
/*
If all tables that has been updated are trans safe then just do rollback.
If not attempt to do remaining updates.
*/
if (trans_safe)
ha_rollback_stmt(thd);
else if (do_update && table_count > 1)
{
/* Add warning here */
VOID(do_updates(0));
}
}
int multi_update::do_updates(bool from_send_error)
{
TABLE_LIST *cur_table;
int local_error;
ha_rows org_updated;
TABLE *table, *tmp_table;
DBUG_ENTER("do_updates");
do_update= 0; // Don't retry this function
if (!found)
DBUG_RETURN(0);
for (cur_table= update_tables; cur_table; cur_table= cur_table->next_local)
{
byte *ref_pos;
table = cur_table->table;
if (table == table_to_update)
continue; // Already updated
org_updated= updated;
tmp_table= tmp_tables[cur_table->shared];
tmp_table->file->extra(HA_EXTRA_CACHE); // Change to read cache
(void) table->file->ha_rnd_init(0);
table->file->extra(HA_EXTRA_NO_CACHE);
/*
Setup copy functions to copy fields from temporary table
*/
List_iterator_fast<Item> field_it(*fields_for_table[cur_table->shared]);
Field **field= tmp_table->field+1; // Skip row pointer
Copy_field *copy_field_ptr= copy_field, *copy_field_end;
for ( ; *field ; field++)
{
Item_field *item= (Item_field* ) field_it++;
(copy_field_ptr++)->set(item->field, *field, 0);
}
copy_field_end=copy_field_ptr;
if ((local_error = tmp_table->file->ha_rnd_init(1)))
goto err;
ref_pos= (byte*) tmp_table->field[0]->ptr;
for (;;)
{
if (thd->killed && trans_safe)
goto err;
if ((local_error=tmp_table->file->rnd_next(tmp_table->record[0])))
{
if (local_error == HA_ERR_END_OF_FILE)
break;
if (local_error == HA_ERR_RECORD_DELETED)
continue; // May happen on dup key
goto err;
}
if ((local_error= table->file->rnd_pos(table->record[0], ref_pos)))
goto err;
table->status|= STATUS_UPDATED;
store_record(table,record[1]);
/* Copy data from temporary table to current table */
for (copy_field_ptr=copy_field;
copy_field_ptr != copy_field_end;
copy_field_ptr++)
(*copy_field_ptr->do_copy)(copy_field_ptr);
if (table->triggers &&
table->triggers->process_triggers(thd, TRG_EVENT_UPDATE,
TRG_ACTION_BEFORE, TRUE))
goto err2;
if (compare_record(table, thd->query_id))
{
if ((local_error=table->file->update_row(table->record[1],
table->record[0])))
{
if (!ignore || local_error != HA_ERR_FOUND_DUPP_KEY)
goto err;
}
updated++;
if (table->triggers &&
table->triggers->process_triggers(thd, TRG_EVENT_UPDATE,
TRG_ACTION_AFTER, TRUE))
goto err2;
}
}
if (updated != org_updated)
{
if (table->file->has_transactions())
transactional_tables= 1;
else
trans_safe= 0; // Can't do safe rollback
}
(void) table->file->ha_rnd_end();
(void) tmp_table->file->ha_rnd_end();
}
DBUG_RETURN(0);
err:
if (!from_send_error)
{
thd->fatal_error();
table->file->print_error(local_error,MYF(0));
}
err2:
(void) table->file->ha_rnd_end();
(void) tmp_table->file->ha_rnd_end();
if (updated != org_updated)
{
if (table->file->has_transactions())
transactional_tables= 1;
else
trans_safe= 0;
}
DBUG_RETURN(1);
}
/* out: 1 if error, 0 if success */
bool multi_update::send_eof()
{
char buff[STRING_BUFFER_USUAL_SIZE];
thd->proc_info="updating reference tables";
/* Does updates for the last n - 1 tables, returns 0 if ok */
int local_error = (table_count) ? do_updates(0) : 0;
thd->proc_info= "end";
/* We must invalidate the query cache before binlog writing and
ha_autocommit_... */
if (updated)
{
query_cache_invalidate3(thd, update_tables, 1);
}
/*
Write the SQL statement to the binlog if we updated
rows and we succeeded or if we updated some non
transactional tables.
*/
if ((local_error == 0) || (updated && !trans_safe))
{
if (mysql_bin_log.is_open())
{
if (local_error == 0)
thd->clear_error();
Query_log_event qinfo(thd, thd->query, thd->query_length,
transactional_tables, FALSE);
if (mysql_bin_log.write(&qinfo) && trans_safe)
local_error= 1; // Rollback update
}
if (!transactional_tables)
thd->options|=OPTION_STATUS_NO_TRANS_UPDATE;
}
if (transactional_tables)
{
if (ha_autocommit_or_rollback(thd, local_error != 0))
local_error=1;
}
if (local_error > 0) // if the above log write did not fail ...
{
/* Safety: If we haven't got an error before (should not happen) */
my_message(ER_UNKNOWN_ERROR, "An error occured in multi-table update",
MYF(0));
return TRUE;
}
sprintf(buff, ER(ER_UPDATE_INFO), (ulong) found, (ulong) updated,
(ulong) thd->cuted_fields);
thd->row_count_func=
(thd->client_capabilities & CLIENT_FOUND_ROWS) ? found : updated;
::send_ok(thd, (ulong) thd->row_count_func,
thd->insert_id_used ? thd->insert_id() : 0L,buff);
return FALSE;
}
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