mariadb/sql/sql_handler.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

767 lines
23 KiB
C++

/* Copyright (C) 2000-2004 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 */
/* HANDLER ... commands - direct access to ISAM */
/* TODO:
HANDLER blabla OPEN [ AS foobar ] [ (column-list) ]
the most natural (easiest, fastest) way to do it is to
compute List<Item> field_list not in mysql_ha_read
but in mysql_ha_open, and then store it in TABLE structure.
The problem here is that mysql_parse calls free_item to free all the
items allocated at the end of every query. The workaround would to
keep two item lists per THD - normal free_list and handler_items.
The second is to be freeed only on thread end. mysql_ha_open should
then do { handler_items=concat(handler_items, free_list); free_list=0; }
But !!! do_command calls free_root at the end of every query and frees up
all the sql_alloc'ed memory. It's harder to work around...
*/
/*
There are two containers holding information about open handler tables.
The first is 'thd->handler_tables'. It is a linked list of TABLE objects.
It is used like 'thd->open_tables' in the table cache. The trick is to
exchange these two lists during open and lock of tables. Thus the normal
table cache code can be used.
The second container is a HASH. It holds objects of the type TABLE_LIST.
Despite its name, no lists of tables but only single structs are hashed
(the 'next' pointer is always NULL). The reason for theis second container
is, that we want handler tables to survive FLUSH TABLE commands. A table
affected by FLUSH TABLE must be closed so that other threads are not
blocked by handler tables still in use. Since we use the normal table cache
functions with 'thd->handler_tables', the closed tables are removed from
this list. Hence we need the original open information for the handler
table in the case that it is used again. This information is handed over
to mysql_ha_open() as a TABLE_LIST. So we store this information in the
second container, where it is not affected by FLUSH TABLE. The second
container is implemented as a hash for performance reasons. Consequently,
we use it not only for re-opening a handler table, but also for the
HANDLER ... READ commands. For this purpose, we store a pointer to the
TABLE structure (in the first container) in the TBALE_LIST object in the
second container. When the table is flushed, the pointer is cleared.
*/
#include "mysql_priv.h"
#include "sql_select.h"
#include <assert.h>
#define HANDLER_TABLES_HASH_SIZE 120
static enum enum_ha_read_modes rkey_to_rnext[]=
{ RNEXT_SAME, RNEXT, RPREV, RNEXT, RPREV, RNEXT, RPREV, RPREV };
#define HANDLER_TABLES_HACK(thd) { \
TABLE *tmp=thd->open_tables; \
thd->open_tables=thd->handler_tables; \
thd->handler_tables=tmp; }
static int mysql_ha_flush_table(THD *thd, TABLE **table_ptr, uint mode_flags);
/*
Get hash key and hash key length.
SYNOPSIS
mysql_ha_hash_get_key()
tables Pointer to the hash object.
key_len_p (out) Pointer to the result for key length.
first Unused.
DESCRIPTION
The hash object is an TABLE_LIST struct.
The hash key is the alias name.
The hash key length is the alias name length plus one for the
terminateing NUL character.
RETURN
Pointer to the TABLE_LIST struct.
*/
static char *mysql_ha_hash_get_key(TABLE_LIST *tables, uint *key_len_p,
my_bool first __attribute__((unused)))
{
*key_len_p= strlen(tables->alias) + 1 ; /* include '\0' in comparisons */
return tables->alias;
}
/*
Free an hash object.
SYNOPSIS
mysql_ha_hash_free()
tables Pointer to the hash object.
DESCRIPTION
The hash object is an TABLE_LIST struct.
RETURN
Nothing
*/
static void mysql_ha_hash_free(TABLE_LIST *tables)
{
my_free((char*) tables, MYF(0));
}
/*
Open a HANDLER table.
SYNOPSIS
mysql_ha_open()
thd Thread identifier.
tables A list of tables with the first entry to open.
reopen Re-open a previously opened handler table.
DESCRIPTION
Though this function takes a list of tables, only the first list entry
will be opened.
'reopen' is set when a handler table is to be re-opened. In this case,
'tables' is the pointer to the hashed TABLE_LIST object which has been
saved on the original open.
'reopen' is also used to suppress the sending of an 'ok' message or
error messages.
RETURN
FALSE OK
TRUE Error
*/
bool mysql_ha_open(THD *thd, TABLE_LIST *tables, bool reopen)
{
TABLE_LIST *hash_tables;
char *db, *name, *alias;
uint dblen, namelen, aliaslen, counter;
int error;
DBUG_ENTER("mysql_ha_open");
DBUG_PRINT("enter",("'%s'.'%s' as '%s' reopen: %d",
tables->db, tables->table_name, tables->alias,
(int) reopen));
if (! hash_inited(&thd->handler_tables_hash))
{
/*
HASH entries are of type TABLE_LIST.
*/
if (hash_init(&thd->handler_tables_hash, &my_charset_latin1,
HANDLER_TABLES_HASH_SIZE, 0, 0,
(hash_get_key) mysql_ha_hash_get_key,
(hash_free_key) mysql_ha_hash_free, 0))
goto err;
}
else if (! reopen) /* Otherwise we have 'tables' already. */
{
if (hash_search(&thd->handler_tables_hash, (byte*) tables->alias,
strlen(tables->alias) + 1))
{
DBUG_PRINT("info",("duplicate '%s'", tables->alias));
if (! reopen)
my_error(ER_NONUNIQ_TABLE, MYF(0), tables->alias);
goto err;
}
}
/*
open_tables() will set 'tables->table' if successful.
It must be NULL for a real open when calling open_tables().
*/
DBUG_ASSERT(! tables->table);
HANDLER_TABLES_HACK(thd);
/* for now HANDLER can be used only for real TABLES */
tables->required_type= FRMTYPE_TABLE;
error= open_tables(thd, &tables, &counter, 0);
HANDLER_TABLES_HACK(thd);
if (error)
goto err;
/* There can be only one table in '*tables'. */
if (! (tables->table->file->table_flags() & HA_CAN_SQL_HANDLER))
{
if (! reopen)
my_error(ER_ILLEGAL_HA, MYF(0), tables->alias);
mysql_ha_close(thd, tables);
goto err;
}
if (! reopen)
{
/* copy the TABLE_LIST struct */
dblen= strlen(tables->db) + 1;
namelen= strlen(tables->table_name) + 1;
aliaslen= strlen(tables->alias) + 1;
if (!(my_multi_malloc(MYF(MY_WME),
&hash_tables, sizeof(*hash_tables),
&db, dblen,
&name, namelen,
&alias, aliaslen,
NullS)))
goto err;
/* structure copy */
*hash_tables= *tables;
hash_tables->db= db;
hash_tables->table_name= name;
hash_tables->alias= alias;
memcpy(hash_tables->db, tables->db, dblen);
memcpy(hash_tables->table_name, tables->table_name, namelen);
memcpy(hash_tables->alias, tables->alias, aliaslen);
/* add to hash */
if (my_hash_insert(&thd->handler_tables_hash, (byte*) hash_tables))
{
mysql_ha_close(thd, tables);
goto err;
}
}
if (! reopen)
send_ok(thd);
DBUG_PRINT("exit",("OK"));
DBUG_RETURN(FALSE);
err:
DBUG_PRINT("exit",("ERROR"));
DBUG_RETURN(TRUE);
}
/*
Close a HANDLER table.
SYNOPSIS
mysql_ha_close()
thd Thread identifier.
tables A list of tables with the first entry to close.
DESCRIPTION
Though this function takes a list of tables, only the first list entry
will be closed. Broadcasts a COND_refresh condition.
RETURN
FALSE ok
TRUE error
*/
bool mysql_ha_close(THD *thd, TABLE_LIST *tables)
{
TABLE_LIST *hash_tables;
TABLE **table_ptr;
DBUG_ENTER("mysql_ha_close");
DBUG_PRINT("enter",("'%s'.'%s' as '%s'",
tables->db, tables->table_name, tables->alias));
if ((hash_tables= (TABLE_LIST*) hash_search(&thd->handler_tables_hash,
(byte*) tables->alias,
strlen(tables->alias) + 1)))
{
/*
Though we could take the table pointer from hash_tables->table,
we must follow the thd->handler_tables chain anyway, as we need the
address of the 'next' pointer referencing this table
for close_thread_table().
*/
for (table_ptr= &(thd->handler_tables);
*table_ptr && (*table_ptr != hash_tables->table);
table_ptr= &(*table_ptr)->next)
;
if (*table_ptr)
{
(*table_ptr)->file->ha_index_or_rnd_end();
VOID(pthread_mutex_lock(&LOCK_open));
if (close_thread_table(thd, table_ptr))
{
/* Tell threads waiting for refresh that something has happened */
VOID(pthread_cond_broadcast(&COND_refresh));
}
VOID(pthread_mutex_unlock(&LOCK_open));
}
hash_delete(&thd->handler_tables_hash, (byte*) hash_tables);
}
else
{
my_error(ER_UNKNOWN_TABLE, MYF(0), tables->alias, "HANDLER");
DBUG_PRINT("exit",("ERROR"));
DBUG_RETURN(TRUE);
}
send_ok(thd);
DBUG_PRINT("exit", ("OK"));
DBUG_RETURN(FALSE);
}
/*
Read from a HANDLER table.
SYNOPSIS
mysql_ha_read()
thd Thread identifier.
tables A list of tables with the first entry to read.
mode
keyname
key_expr
ha_rkey_mode
cond
select_limit_cnt
offset_limit_cnt
RETURN
FALSE ok
TRUE error
*/
bool mysql_ha_read(THD *thd, TABLE_LIST *tables,
enum enum_ha_read_modes mode, char *keyname,
List<Item> *key_expr,
enum ha_rkey_function ha_rkey_mode, Item *cond,
ha_rows select_limit_cnt, ha_rows offset_limit_cnt)
{
TABLE_LIST *hash_tables;
TABLE **table_ptr;
TABLE *table;
MYSQL_LOCK *lock;
List<Item> list;
Protocol *protocol= thd->protocol;
char buff[MAX_FIELD_WIDTH];
String buffer(buff, sizeof(buff), system_charset_info);
int error, keyno= -1;
uint num_rows;
byte *key;
uint key_len;
bool not_used;
DBUG_ENTER("mysql_ha_read");
DBUG_PRINT("enter",("'%s'.'%s' as '%s'",
tables->db, tables->table_name, tables->alias));
LINT_INIT(key);
LINT_INIT(key_len);
thd->lex->select_lex.context.resolve_in_table_list_only(tables);
list.push_front(new Item_field(&thd->lex->select_lex.context,
NULL, NULL, "*"));
List_iterator<Item> it(list);
it++;
if ((hash_tables= (TABLE_LIST*) hash_search(&thd->handler_tables_hash,
(byte*) tables->alias,
strlen(tables->alias) + 1)))
{
table= hash_tables->table;
DBUG_PRINT("info-in-hash",("'%s'.'%s' as '%s' tab %p",
hash_tables->db, hash_tables->table_name,
hash_tables->alias, table));
/* Table might have been flushed. */
if (table && (table->s->version != refresh_version))
{
/*
We must follow the thd->handler_tables chain, as we need the
address of the 'next' pointer referencing this table
for close_thread_table().
*/
for (table_ptr= &(thd->handler_tables);
*table_ptr && (*table_ptr != table);
table_ptr= &(*table_ptr)->next)
{}
(*table_ptr)->file->ha_index_or_rnd_end();
VOID(pthread_mutex_lock(&LOCK_open));
if (close_thread_table(thd, table_ptr))
{
/* Tell threads waiting for refresh that something has happened */
VOID(pthread_cond_broadcast(&COND_refresh));
}
VOID(pthread_mutex_unlock(&LOCK_open));
table= hash_tables->table= NULL;
}
if (!table)
{
/*
The handler table has been closed. Re-open it.
*/
if (mysql_ha_open(thd, hash_tables, 1))
{
DBUG_PRINT("exit",("reopen failed"));
goto err0;
}
table= hash_tables->table;
DBUG_PRINT("info",("re-opened '%s'.'%s' as '%s' tab %p",
hash_tables->db, hash_tables->table_name,
hash_tables->alias, table));
}
#if MYSQL_VERSION_ID < 40100
if (*tables->db && strcmp(table->table_cache_key, tables->db))
{
DBUG_PRINT("info",("wrong db"));
table= NULL;
}
#endif
}
else
table= NULL;
if (!table)
{
#if MYSQL_VERSION_ID < 40100
char buff[MAX_DBKEY_LENGTH];
if (*tables->db)
strxnmov(buff, sizeof(buff)-1, tables->db, ".", tables->table_name,
NullS);
else
strncpy(buff, tables->alias, sizeof(buff));
my_error(ER_UNKNOWN_TABLE, MYF(0), buff, "HANDLER");
#else
my_error(ER_UNKNOWN_TABLE, MYF(0), tables->alias, "HANDLER");
#endif
goto err0;
}
tables->table=table;
if (cond && ((!cond->fixed &&
cond->fix_fields(thd, &cond)) || cond->check_cols(1)))
goto err0;
if (keyname)
{
if ((keyno=find_type(keyname, &table->s->keynames, 1+2)-1)<0)
{
my_error(ER_KEY_DOES_NOT_EXITS, MYF(0), keyname, tables->alias);
goto err0;
}
}
if (insert_fields(thd, &thd->lex->select_lex.context,
tables->db, tables->alias, &it, 0))
goto err0;
protocol->send_fields(&list, Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF);
HANDLER_TABLES_HACK(thd);
lock= mysql_lock_tables(thd, &tables->table, 1, 0, &not_used);
HANDLER_TABLES_HACK(thd);
if (!lock)
goto err0; // mysql_lock_tables() printed error message already
/*
In ::external_lock InnoDB resets the fields which tell it that
the handle is used in the HANDLER interface. Tell it again that
we are using it for HANDLER.
*/
table->file->init_table_handle_for_HANDLER();
for (num_rows=0; num_rows < select_limit_cnt; )
{
switch (mode) {
case RNEXT:
if (table->file->inited != handler::NONE)
{
error=keyname ?
table->file->index_next(table->record[0]) :
table->file->rnd_next(table->record[0]);
break;
}
/* else fall through */
case RFIRST:
if (keyname)
{
table->file->ha_index_or_rnd_end();
table->file->ha_index_init(keyno, 1);
error= table->file->index_first(table->record[0]);
}
else
{
table->file->ha_index_or_rnd_end();
if (!(error= table->file->ha_rnd_init(1)))
error= table->file->rnd_next(table->record[0]);
}
mode=RNEXT;
break;
case RPREV:
DBUG_ASSERT(keyname != 0);
if (table->file->inited != handler::NONE)
{
error=table->file->index_prev(table->record[0]);
break;
}
/* else fall through */
case RLAST:
DBUG_ASSERT(keyname != 0);
table->file->ha_index_or_rnd_end();
table->file->ha_index_init(keyno, 1);
error= table->file->index_last(table->record[0]);
mode=RPREV;
break;
case RNEXT_SAME:
/* Continue scan on "(keypart1,keypart2,...)=(c1, c2, ...) */
DBUG_ASSERT(keyname != 0);
error= table->file->index_next_same(table->record[0], key, key_len);
break;
case RKEY:
{
DBUG_ASSERT(keyname != 0);
KEY *keyinfo=table->key_info+keyno;
KEY_PART_INFO *key_part=keyinfo->key_part;
if (key_expr->elements > keyinfo->key_parts)
{
my_error(ER_TOO_MANY_KEY_PARTS, MYF(0), keyinfo->key_parts);
goto err;
}
List_iterator<Item> it_ke(*key_expr);
Item *item;
for (key_len=0 ; (item=it_ke++) ; key_part++)
{
// 'item' can be changed by fix_fields() call
if ((!item->fixed &&
item->fix_fields(thd, it_ke.ref())) ||
(item= *it_ke.ref())->check_cols(1))
goto err;
if (item->used_tables() & ~RAND_TABLE_BIT)
{
my_error(ER_WRONG_ARGUMENTS,MYF(0),"HANDLER ... READ");
goto err;
}
(void) item->save_in_field(key_part->field, 1);
key_len+=key_part->store_length;
}
if (!(key= (byte*) thd->calloc(ALIGN_SIZE(key_len))))
goto err;
table->file->ha_index_or_rnd_end();
table->file->ha_index_init(keyno, 1);
key_copy(key, table->record[0], table->key_info + keyno, key_len);
error= table->file->index_read(table->record[0],
key,key_len,ha_rkey_mode);
mode=rkey_to_rnext[(int)ha_rkey_mode];
break;
}
default:
my_message(ER_ILLEGAL_HA, ER(ER_ILLEGAL_HA), MYF(0));
goto err;
}
if (error)
{
if (error == HA_ERR_RECORD_DELETED)
continue;
if (error != HA_ERR_KEY_NOT_FOUND && error != HA_ERR_END_OF_FILE)
{
sql_print_error("mysql_ha_read: Got error %d when reading table '%s'",
error, tables->table_name);
table->file->print_error(error,MYF(0));
goto err;
}
goto ok;
}
if (cond && !cond->val_int())
continue;
if (num_rows >= offset_limit_cnt)
{
Item *item;
protocol->prepare_for_resend();
it.rewind();
while ((item=it++))
{
if (item->send(thd->protocol, &buffer))
{
protocol->free(); // Free used
my_message(ER_OUT_OF_RESOURCES, ER(ER_OUT_OF_RESOURCES), MYF(0));
goto err;
}
}
protocol->write();
}
num_rows++;
}
ok:
mysql_unlock_tables(thd,lock);
send_eof(thd);
DBUG_PRINT("exit",("OK"));
DBUG_RETURN(FALSE);
err:
mysql_unlock_tables(thd,lock);
err0:
DBUG_PRINT("exit",("ERROR"));
DBUG_RETURN(TRUE);
}
/*
Flush (close) a list of HANDLER tables.
SYNOPSIS
mysql_ha_flush()
thd Thread identifier.
tables The list of tables to close. If NULL,
close all HANDLER tables [marked as flushed].
mode_flags MYSQL_HA_CLOSE_FINAL finally close the table.
MYSQL_HA_REOPEN_ON_USAGE mark for reopen.
MYSQL_HA_FLUSH_ALL flush all tables, not only
those marked for flush.
is_locked If LOCK_open is locked.
DESCRIPTION
The list of HANDLER tables may be NULL, in which case all HANDLER
tables are closed (if MYSQL_HA_FLUSH_ALL) is set.
If 'tables' is NULL and MYSQL_HA_FLUSH_ALL is not set,
all HANDLER tables marked for flush are closed.
Broadcasts a COND_refresh condition, for every table closed.
NOTE
Since mysql_ha_flush() is called when the base table has to be closed,
we compare real table names, not aliases. Hence, database names matter.
RETURN
0 ok
*/
int mysql_ha_flush(THD *thd, TABLE_LIST *tables, uint mode_flags,
bool is_locked)
{
TABLE_LIST *tmp_tables;
TABLE **table_ptr;
bool did_lock= FALSE;
DBUG_ENTER("mysql_ha_flush");
DBUG_PRINT("enter", ("tables: %p mode_flags: 0x%02x", tables, mode_flags));
if (tables)
{
/* Close all tables in the list. */
for (tmp_tables= tables ; tmp_tables; tmp_tables= tmp_tables->next_local)
{
DBUG_PRINT("info-in-tables-list",("'%s'.'%s' as '%s'",
tmp_tables->db, tmp_tables->table_name,
tmp_tables->alias));
/* Close all currently open handler tables with the same base table. */
table_ptr= &(thd->handler_tables);
while (*table_ptr)
{
if ((!*tmp_tables->db ||
!my_strcasecmp(&my_charset_latin1, (*table_ptr)->s->db.str,
tmp_tables->db)) &&
! my_strcasecmp(&my_charset_latin1,
(*table_ptr)->s->table_name.str,
tmp_tables->table_name))
{
DBUG_PRINT("info",("*table_ptr '%s'.'%s' as '%s'",
(*table_ptr)->s->db.str,
(*table_ptr)->s->table_name.str,
(*table_ptr)->alias));
/* The first time it is required, lock for close_thread_table(). */
if (! did_lock && ! is_locked)
{
VOID(pthread_mutex_lock(&LOCK_open));
did_lock= TRUE;
}
mysql_ha_flush_table(thd, table_ptr, mode_flags);
continue;
}
table_ptr= &(*table_ptr)->next;
}
/* end of handler_tables list */
}
/* end of flush tables list */
}
else
{
/* Close all currently open tables [which are marked for flush]. */
table_ptr= &(thd->handler_tables);
while (*table_ptr)
{
if ((mode_flags & MYSQL_HA_FLUSH_ALL) ||
((*table_ptr)->s->version != refresh_version))
{
/* The first time it is required, lock for close_thread_table(). */
if (! did_lock && ! is_locked)
{
VOID(pthread_mutex_lock(&LOCK_open));
did_lock= TRUE;
}
mysql_ha_flush_table(thd, table_ptr, mode_flags);
continue;
}
table_ptr= &(*table_ptr)->next;
}
}
/* Release the lock if it was taken by this function. */
if (did_lock)
VOID(pthread_mutex_unlock(&LOCK_open));
DBUG_RETURN(0);
}
/*
Flush (close) a table.
SYNOPSIS
mysql_ha_flush_table()
thd Thread identifier.
table The table to close.
mode_flags MYSQL_HA_CLOSE_FINAL finally close the table.
MYSQL_HA_REOPEN_ON_USAGE mark for reopen.
DESCRIPTION
Broadcasts a COND_refresh condition, for every table closed.
The caller must lock LOCK_open.
RETURN
0 ok
*/
static int mysql_ha_flush_table(THD *thd, TABLE **table_ptr, uint mode_flags)
{
TABLE_LIST *hash_tables;
TABLE *table= *table_ptr;
DBUG_ENTER("mysql_ha_flush_table");
DBUG_PRINT("enter",("'%s'.'%s' as '%s' flags: 0x%02x",
table->s->db.str, table->s->table_name.str,
table->alias, mode_flags));
if ((hash_tables= (TABLE_LIST*) hash_search(&thd->handler_tables_hash,
(byte*) table->alias,
strlen(table->alias) + 1)))
{
if (! (mode_flags & MYSQL_HA_REOPEN_ON_USAGE))
{
/* This is a final close. Remove from hash. */
hash_delete(&thd->handler_tables_hash, (byte*) hash_tables);
}
else
{
/* Mark table as closed, ready for re-open. */
hash_tables->table= NULL;
}
}
safe_mutex_assert_owner(&LOCK_open);
(*table_ptr)->file->ha_index_or_rnd_end();
safe_mutex_assert_owner(&LOCK_open);
if (close_thread_table(thd, table_ptr))
{
/* Tell threads waiting for refresh that something has happened */
VOID(pthread_cond_broadcast(&COND_refresh));
}
DBUG_RETURN(0);
}