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	in the MDL deadlock detector". It is no longer needed as a better fix for this bug has been pushed.
		
			
				
	
	
		
			579 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			579 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
/* Copyright 2006-2008 MySQL AB, 2008-2009 Sun Microsystems, Inc.
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   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU General Public License as published by
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   the Free Software Foundation; version 2 of the License.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU General Public License for more details.
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   You should have received a copy of the GNU General Public License
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   along with this program; if not, write to the Free Software
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   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA */
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#ifndef SQL_BASE_INCLUDED
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#define SQL_BASE_INCLUDED
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#include "unireg.h"                    // REQUIRED: for other includes
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#include "sql_trigger.h"                        /* trg_event_type */
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#include "sql_class.h"                          /* enum_mark_columns */
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#include "mysqld.h"                             /* key_map */
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class Item_ident;
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struct Name_resolution_context;
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class Open_table_context;
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class Open_tables_state;
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class Prelocking_strategy;
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struct TABLE_LIST;
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class THD;
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struct handlerton;
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struct TABLE;
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typedef class st_select_lex SELECT_LEX;
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typedef struct st_lock_param_type ALTER_PARTITION_PARAM_TYPE;
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/*
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  This enumeration type is used only by the function find_item_in_list
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  to return the info on how an item has been resolved against a list
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  of possibly aliased items.
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  The item can be resolved:
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   - against an alias name of the list's element (RESOLVED_AGAINST_ALIAS)
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   - against non-aliased field name of the list  (RESOLVED_WITH_NO_ALIAS)
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   - against an aliased field name of the list   (RESOLVED_BEHIND_ALIAS)
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   - ignoring the alias name in cases when SQL requires to ignore aliases
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     (e.g. when the resolved field reference contains a table name or
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     when the resolved item is an expression)   (RESOLVED_IGNORING_ALIAS)
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*/
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enum enum_resolution_type {
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  NOT_RESOLVED=0,
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  RESOLVED_IGNORING_ALIAS,
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  RESOLVED_BEHIND_ALIAS,
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  RESOLVED_WITH_NO_ALIAS,
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  RESOLVED_AGAINST_ALIAS
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};
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enum find_item_error_report_type {REPORT_ALL_ERRORS, REPORT_EXCEPT_NOT_FOUND,
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				  IGNORE_ERRORS, REPORT_EXCEPT_NON_UNIQUE,
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                                  IGNORE_EXCEPT_NON_UNIQUE};
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enum enum_tdc_remove_table_type {TDC_RT_REMOVE_ALL, TDC_RT_REMOVE_NOT_OWN,
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                                 TDC_RT_REMOVE_UNUSED};
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/* bits for last argument to remove_table_from_cache() */
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#define RTFC_NO_FLAG                0x0000
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#define RTFC_OWNED_BY_THD_FLAG      0x0001
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#define RTFC_WAIT_OTHER_THREAD_FLAG 0x0002
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#define RTFC_CHECK_KILLED_FLAG      0x0004
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bool check_dup(const char *db, const char *name, TABLE_LIST *tables);
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extern mysql_mutex_t LOCK_open;
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bool table_cache_init(void);
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void table_cache_free(void);
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bool table_def_init(void);
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void table_def_free(void);
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void table_def_start_shutdown(void);
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void assign_new_table_id(TABLE_SHARE *share);
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uint cached_open_tables(void);
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uint cached_table_definitions(void);
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uint create_table_def_key(THD *thd, char *key,
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                          const TABLE_LIST *table_list,
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                          bool tmp_table);
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TABLE_SHARE *get_table_share(THD *thd, TABLE_LIST *table_list, char *key,
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                             uint key_length, uint db_flags, int *error,
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                             my_hash_value_type hash_value);
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void release_table_share(TABLE_SHARE *share);
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TABLE_SHARE *get_cached_table_share(const char *db, const char *table_name);
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TABLE *open_ltable(THD *thd, TABLE_LIST *table_list, thr_lock_type update,
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                   uint lock_flags);
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/* mysql_lock_tables() and open_table() flags bits */
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#define MYSQL_OPEN_IGNORE_GLOBAL_READ_LOCK      0x0001
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#define MYSQL_OPEN_IGNORE_FLUSH                 0x0002
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#define MYSQL_OPEN_TEMPORARY_ONLY               0x0004
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#define MYSQL_LOCK_IGNORE_GLOBAL_READ_ONLY      0x0008
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#define MYSQL_LOCK_LOG_TABLE                    0x0010
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/**
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  Do not try to acquire a metadata lock on the table: we
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  already have one.
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*/
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#define MYSQL_OPEN_HAS_MDL_LOCK                 0x0020
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/**
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  If in locked tables mode, ignore the locked tables and get
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  a new instance of the table.
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*/
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#define MYSQL_OPEN_GET_NEW_TABLE                0x0040
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/** Don't look up the table in the list of temporary tables. */
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#define MYSQL_OPEN_SKIP_TEMPORARY               0x0080
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/** Fail instead of waiting when conficting metadata lock is discovered. */
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#define MYSQL_OPEN_FAIL_ON_MDL_CONFLICT         0x0100
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/** Open tables using MDL_SHARED lock instead of one specified in parser. */
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#define MYSQL_OPEN_FORCE_SHARED_MDL             0x0200
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/**
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  Open tables using MDL_SHARED_HIGH_PRIO lock instead of one specified
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  in parser.
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*/
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#define MYSQL_OPEN_FORCE_SHARED_HIGH_PRIO_MDL   0x0400
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/**
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  When opening or locking the table, use the maximum timeout
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  (LONG_TIMEOUT = 1 year) rather than the user-supplied timeout value.
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*/
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#define MYSQL_LOCK_IGNORE_TIMEOUT               0x0800
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/**
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  When acquiring "strong" (SNW, SNRW, X) metadata locks on tables to
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  be open do not acquire global and schema-scope IX locks.
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*/
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#define MYSQL_OPEN_SKIP_SCOPED_MDL_LOCK         0x1000
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/** Please refer to the internals manual. */
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#define MYSQL_OPEN_REOPEN  (MYSQL_OPEN_IGNORE_FLUSH |\
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                            MYSQL_OPEN_IGNORE_GLOBAL_READ_LOCK |\
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                            MYSQL_LOCK_IGNORE_GLOBAL_READ_ONLY |\
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                            MYSQL_LOCK_IGNORE_TIMEOUT |\
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                            MYSQL_OPEN_GET_NEW_TABLE |\
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                            MYSQL_OPEN_SKIP_TEMPORARY |\
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                            MYSQL_OPEN_HAS_MDL_LOCK)
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bool open_table(THD *thd, TABLE_LIST *table_list, MEM_ROOT *mem_root,
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                Open_table_context *ot_ctx);
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bool open_new_frm(THD *thd, TABLE_SHARE *share, const char *alias,
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                  uint db_stat, uint prgflag,
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                  uint ha_open_flags, TABLE *outparam, TABLE_LIST *table_desc,
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                  MEM_ROOT *mem_root);
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bool get_key_map_from_key_list(key_map *map, TABLE *table,
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                               List<String> *index_list);
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TABLE *open_table_uncached(THD *thd, const char *path, const char *db,
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			   const char *table_name,
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                           bool add_to_temporary_tables_list);
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TABLE *find_locked_table(TABLE *list, const char *db, const char *table_name);
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TABLE *find_write_locked_table(TABLE *list, const char *db,
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                               const char *table_name);
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thr_lock_type read_lock_type_for_table(THD *thd,
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                                       Query_tables_list *prelocking_ctx,
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                                       TABLE_LIST *table_list);
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my_bool mysql_rm_tmp_tables(void);
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bool rm_temporary_table(handlerton *base, char *path);
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void close_tables_for_reopen(THD *thd, TABLE_LIST **tables,
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                             MDL_ticket *start_of_statement_svp);
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TABLE_LIST *find_table_in_list(TABLE_LIST *table,
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                               TABLE_LIST *TABLE_LIST::*link,
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                               const char *db_name,
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                               const char *table_name);
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TABLE *find_temporary_table(THD *thd, const char *db, const char *table_name);
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TABLE *find_temporary_table(THD *thd, const TABLE_LIST *tl);
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TABLE *find_temporary_table(THD *thd, const char *table_key,
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                            uint table_key_length);
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void close_thread_tables(THD *thd);
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bool fill_record_n_invoke_before_triggers(THD *thd, List<Item> &fields,
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                                          List<Item> &values,
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                                          bool ignore_errors,
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                                          Table_triggers_list *triggers,
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                                          enum trg_event_type event);
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bool fill_record_n_invoke_before_triggers(THD *thd, Field **field,
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                                          List<Item> &values,
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                                          bool ignore_errors,
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                                          Table_triggers_list *triggers,
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                                          enum trg_event_type event);
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bool insert_fields(THD *thd, Name_resolution_context *context,
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		   const char *db_name, const char *table_name,
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                   List_iterator<Item> *it, bool any_privileges);
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int setup_wild(THD *thd, TABLE_LIST *tables, List<Item> &fields,
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	       List<Item> *sum_func_list, uint wild_num);
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bool setup_fields(THD *thd, Item** ref_pointer_array,
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                  List<Item> &item, enum_mark_columns mark_used_columns,
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                  List<Item> *sum_func_list, bool allow_sum_func);
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bool fill_record(THD *thd, Field **field, List<Item> &values,
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                 bool ignore_errors);
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Field *
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find_field_in_tables(THD *thd, Item_ident *item,
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                     TABLE_LIST *first_table, TABLE_LIST *last_table,
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                     Item **ref, find_item_error_report_type report_error,
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                     bool check_privileges, bool register_tree_change);
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Field *
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find_field_in_table_ref(THD *thd, TABLE_LIST *table_list,
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                        const char *name, uint length,
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                        const char *item_name, const char *db_name,
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                        const char *table_name, Item **ref,
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                        bool check_privileges, bool allow_rowid,
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                        uint *cached_field_index_ptr,
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                        bool register_tree_change, TABLE_LIST **actual_table);
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Field *
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find_field_in_table(THD *thd, TABLE *table, const char *name, uint length,
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                    bool allow_rowid, uint *cached_field_index_ptr);
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Field *
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find_field_in_table_sef(TABLE *table, const char *name);
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Item ** find_item_in_list(Item *item, List<Item> &items, uint *counter,
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                          find_item_error_report_type report_error,
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                          enum_resolution_type *resolution);
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bool setup_tables(THD *thd, Name_resolution_context *context,
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                  List<TABLE_LIST> *from_clause, TABLE_LIST *tables,
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                  TABLE_LIST **leaves, bool select_insert);
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bool setup_tables_and_check_access(THD *thd,
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                                   Name_resolution_context *context,
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                                   List<TABLE_LIST> *from_clause,
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                                   TABLE_LIST *tables,
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                                   TABLE_LIST **leaves,
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                                   bool select_insert,
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                                   ulong want_access_first,
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                                   ulong want_access);
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bool wait_while_table_is_used(THD *thd, TABLE *table,
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                              enum ha_extra_function function);
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void drop_open_table(THD *thd, TABLE *table, const char *db_name,
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                     const char *table_name);
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void update_non_unique_table_error(TABLE_LIST *update,
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                                   const char *operation,
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                                   TABLE_LIST *duplicate);
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int setup_conds(THD *thd, TABLE_LIST *tables, TABLE_LIST *leaves,
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		COND **conds);
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int setup_ftfuncs(SELECT_LEX* select);
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int init_ftfuncs(THD *thd, SELECT_LEX* select, bool no_order);
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bool lock_table_names(THD *thd, TABLE_LIST *table_list,
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                      TABLE_LIST *table_list_end, ulong lock_wait_timeout,
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                      uint flags);
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bool open_tables(THD *thd, TABLE_LIST **tables, uint *counter, uint flags,
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                 Prelocking_strategy *prelocking_strategy);
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/* open_and_lock_tables with optional derived handling */
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bool open_and_lock_tables(THD *thd, TABLE_LIST *tables,
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                          bool derived, uint flags,
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                          Prelocking_strategy *prelocking_strategy);
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int open_and_lock_tables_derived(THD *thd, TABLE_LIST *tables, bool derived);
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/* simple open_and_lock_tables without derived handling for single table */
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TABLE *open_n_lock_single_table(THD *thd, TABLE_LIST *table_l,
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                                thr_lock_type lock_type, uint flags,
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                                Prelocking_strategy *prelocking_strategy);
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bool open_normal_and_derived_tables(THD *thd, TABLE_LIST *tables, uint flags);
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bool lock_tables(THD *thd, TABLE_LIST *tables, uint counter, uint flags);
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int decide_logging_format(THD *thd, TABLE_LIST *tables);
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void free_io_cache(TABLE *entry);
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void intern_close_table(TABLE *entry);
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bool close_thread_table(THD *thd, TABLE **table_ptr);
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bool close_temporary_tables(THD *thd);
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TABLE_LIST *unique_table(THD *thd, TABLE_LIST *table, TABLE_LIST *table_list,
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                         bool check_alias);
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int drop_temporary_table(THD *thd, TABLE_LIST *table_list, bool *is_trans);
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void close_temporary_table(THD *thd, TABLE *table, bool free_share,
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                           bool delete_table);
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void close_temporary(TABLE *table, bool free_share, bool delete_table);
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bool rename_temporary_table(THD* thd, TABLE *table, const char *new_db,
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			    const char *table_name);
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bool is_equal(const LEX_STRING *a, const LEX_STRING *b);
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 | 
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/* Functions to work with system tables. */
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bool open_system_tables_for_read(THD *thd, TABLE_LIST *table_list,
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                                 Open_tables_backup *backup);
 | 
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void close_system_tables(THD *thd, Open_tables_backup *backup);
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void close_mysql_tables(THD *thd);
 | 
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TABLE *open_system_table_for_update(THD *thd, TABLE_LIST *one_table);
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TABLE *open_log_table(THD *thd, TABLE_LIST *one_table, Open_tables_backup *backup);
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void close_log_table(THD *thd, Open_tables_backup *backup);
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TABLE *open_performance_schema_table(THD *thd, TABLE_LIST *one_table,
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                                     Open_tables_state *backup);
 | 
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void close_performance_schema_table(THD *thd, Open_tables_state *backup);
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bool close_cached_tables(THD *thd, TABLE_LIST *tables,
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                         bool wait_for_refresh, ulong timeout);
 | 
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bool close_cached_connection_tables(THD *thd, LEX_STRING *connect_string);
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void close_all_tables_for_name(THD *thd, TABLE_SHARE *share,
 | 
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                               bool remove_from_locked_tables);
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OPEN_TABLE_LIST *list_open_tables(THD *thd, const char *db, const char *wild);
 | 
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void tdc_remove_table(THD *thd, enum_tdc_remove_table_type remove_type,
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                      const char *db, const char *table_name,
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                      bool has_lock);
 | 
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bool tdc_open_view(THD *thd, TABLE_LIST *table_list, const char *alias,
 | 
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                   char *cache_key, uint cache_key_length,
 | 
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                   MEM_ROOT *mem_root, uint flags);
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void tdc_flush_unused_tables();
 | 
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TABLE *find_table_for_mdl_upgrade(TABLE *list, const char *db,
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                                  const char *table_name,
 | 
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                                  bool no_error);
 | 
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void mark_tmp_table_for_reuse(TABLE *table);
 | 
						|
bool check_if_table_exists(THD *thd, TABLE_LIST *table, bool *exists);
 | 
						|
 | 
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extern TABLE *unused_tables;
 | 
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extern Item **not_found_item;
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extern Field *not_found_field;
 | 
						|
extern Field *view_ref_found;
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						|
extern HASH table_def_cache;
 | 
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 | 
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/**
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						|
  clean/setup table fields and map.
 | 
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 | 
						|
  @param table        TABLE structure pointer (which should be setup)
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						|
  @param table_list   TABLE_LIST structure pointer (owner of TABLE)
 | 
						|
  @param tablenr     table number
 | 
						|
*/
 | 
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 | 
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 | 
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inline void setup_table_map(TABLE *table, TABLE_LIST *table_list, uint tablenr)
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{
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  table->used_fields= 0;
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  table->const_table= 0;
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  table->null_row= 0;
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  table->status= STATUS_NO_RECORD;
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  table->maybe_null= table_list->outer_join;
 | 
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  TABLE_LIST *embedding= table_list->embedding;
 | 
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  while (!table->maybe_null && embedding)
 | 
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  {
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    table->maybe_null= embedding->outer_join;
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    embedding= embedding->embedding;
 | 
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  }
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  table->tablenr= tablenr;
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  table->map= (table_map) 1 << tablenr;
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  table->force_index= table_list->force_index;
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  table->force_index_order= table->force_index_group= 0;
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  table->covering_keys= table->s->keys_for_keyread;
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  table->merge_keys.clear_all();
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}
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 | 
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inline TABLE_LIST *find_table_in_global_list(TABLE_LIST *table,
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						|
                                             const char *db_name,
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                                             const char *table_name)
 | 
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{
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  return find_table_in_list(table, &TABLE_LIST::next_global,
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                            db_name, table_name);
 | 
						|
}
 | 
						|
 | 
						|
inline TABLE_LIST *find_table_in_local_list(TABLE_LIST *table,
 | 
						|
                                            const char *db_name,
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						|
                                            const char *table_name)
 | 
						|
{
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						|
  return find_table_in_list(table, &TABLE_LIST::next_local,
 | 
						|
                            db_name, table_name);
 | 
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}
 | 
						|
 | 
						|
 | 
						|
inline bool setup_fields_with_no_wrap(THD *thd, Item **ref_pointer_array,
 | 
						|
                                      List<Item> &item,
 | 
						|
                                      enum_mark_columns mark_used_columns,
 | 
						|
                                      List<Item> *sum_func_list,
 | 
						|
                                      bool allow_sum_func)
 | 
						|
{
 | 
						|
  bool res;
 | 
						|
  thd->lex->select_lex.no_wrap_view_item= TRUE;
 | 
						|
  res= setup_fields(thd, ref_pointer_array, item, mark_used_columns,
 | 
						|
                    sum_func_list, allow_sum_func);
 | 
						|
  thd->lex->select_lex.no_wrap_view_item= FALSE;
 | 
						|
  return res;
 | 
						|
}
 | 
						|
 | 
						|
/**
 | 
						|
  An abstract class for a strategy specifying how the prelocking
 | 
						|
  algorithm should extend the prelocking set while processing
 | 
						|
  already existing elements in the set.
 | 
						|
*/
 | 
						|
 | 
						|
class Prelocking_strategy
 | 
						|
{
 | 
						|
public:
 | 
						|
  virtual ~Prelocking_strategy() { }
 | 
						|
 | 
						|
  virtual bool handle_routine(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                              Sroutine_hash_entry *rt, sp_head *sp,
 | 
						|
                              bool *need_prelocking) = 0;
 | 
						|
  virtual bool handle_table(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                            TABLE_LIST *table_list, bool *need_prelocking) = 0;
 | 
						|
  virtual bool handle_view(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                           TABLE_LIST *table_list, bool *need_prelocking)= 0;
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  A Strategy for prelocking algorithm suitable for DML statements.
 | 
						|
 | 
						|
  Ensures that all tables used by all statement's SF/SP/triggers and
 | 
						|
  required for foreign key checks are prelocked and SF/SPs used are
 | 
						|
  cached.
 | 
						|
*/
 | 
						|
 | 
						|
class DML_prelocking_strategy : public Prelocking_strategy
 | 
						|
{
 | 
						|
public:
 | 
						|
  virtual bool handle_routine(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                              Sroutine_hash_entry *rt, sp_head *sp,
 | 
						|
                              bool *need_prelocking);
 | 
						|
  virtual bool handle_table(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                            TABLE_LIST *table_list, bool *need_prelocking);
 | 
						|
  virtual bool handle_view(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                           TABLE_LIST *table_list, bool *need_prelocking);
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  A strategy for prelocking algorithm to be used for LOCK TABLES
 | 
						|
  statement.
 | 
						|
*/
 | 
						|
 | 
						|
class Lock_tables_prelocking_strategy : public DML_prelocking_strategy
 | 
						|
{
 | 
						|
  virtual bool handle_table(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                            TABLE_LIST *table_list, bool *need_prelocking);
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  Strategy for prelocking algorithm to be used for ALTER TABLE statements.
 | 
						|
 | 
						|
  Unlike DML or LOCK TABLES strategy, it doesn't
 | 
						|
  prelock triggers, views or stored routines, since they are not
 | 
						|
  used during ALTER.
 | 
						|
*/
 | 
						|
 | 
						|
class Alter_table_prelocking_strategy : public Prelocking_strategy
 | 
						|
{
 | 
						|
public:
 | 
						|
 | 
						|
  Alter_table_prelocking_strategy(Alter_info *alter_info)
 | 
						|
    : m_alter_info(alter_info)
 | 
						|
  {}
 | 
						|
 | 
						|
  virtual bool handle_routine(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                              Sroutine_hash_entry *rt, sp_head *sp,
 | 
						|
                              bool *need_prelocking);
 | 
						|
  virtual bool handle_table(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                            TABLE_LIST *table_list, bool *need_prelocking);
 | 
						|
  virtual bool handle_view(THD *thd, Query_tables_list *prelocking_ctx,
 | 
						|
                           TABLE_LIST *table_list, bool *need_prelocking);
 | 
						|
 | 
						|
private:
 | 
						|
  Alter_info *m_alter_info;
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
inline bool
 | 
						|
open_tables(THD *thd, TABLE_LIST **tables, uint *counter, uint flags)
 | 
						|
{
 | 
						|
  DML_prelocking_strategy prelocking_strategy;
 | 
						|
 | 
						|
  return open_tables(thd, tables, counter, flags, &prelocking_strategy);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
inline TABLE *open_n_lock_single_table(THD *thd, TABLE_LIST *table_l,
 | 
						|
                                       thr_lock_type lock_type, uint flags)
 | 
						|
{
 | 
						|
  DML_prelocking_strategy prelocking_strategy;
 | 
						|
 | 
						|
  return open_n_lock_single_table(thd, table_l, lock_type, flags,
 | 
						|
                                  &prelocking_strategy);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/* open_and_lock_tables with derived handling */
 | 
						|
inline bool open_and_lock_tables(THD *thd, TABLE_LIST *tables,
 | 
						|
                                 bool derived, uint flags)
 | 
						|
{
 | 
						|
  DML_prelocking_strategy prelocking_strategy;
 | 
						|
 | 
						|
  return open_and_lock_tables(thd, tables, derived, flags,
 | 
						|
                              &prelocking_strategy);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  A context of open_tables() function, used to recover
 | 
						|
  from a failed open_table() or open_routine() attempt.
 | 
						|
*/
 | 
						|
 | 
						|
class Open_table_context
 | 
						|
{
 | 
						|
public:
 | 
						|
  enum enum_open_table_action
 | 
						|
  {
 | 
						|
    OT_NO_ACTION= 0,
 | 
						|
    OT_BACKOFF_AND_RETRY,
 | 
						|
    OT_REOPEN_TABLES,
 | 
						|
    OT_DISCOVER,
 | 
						|
    OT_REPAIR
 | 
						|
  };
 | 
						|
  Open_table_context(THD *thd, uint flags);
 | 
						|
 | 
						|
  bool recover_from_failed_open(THD *thd);
 | 
						|
  bool request_backoff_action(enum_open_table_action action_arg,
 | 
						|
                              TABLE_LIST *table);
 | 
						|
 | 
						|
  bool can_recover_from_failed_open() const
 | 
						|
  { return m_action != OT_NO_ACTION; }
 | 
						|
 | 
						|
  /**
 | 
						|
    When doing a back-off, we close all tables acquired by this
 | 
						|
    statement.  Return an MDL savepoint taken at the beginning of
 | 
						|
    the statement, so that we can rollback to it before waiting on
 | 
						|
    locks.
 | 
						|
  */
 | 
						|
  MDL_ticket *start_of_statement_svp() const
 | 
						|
  {
 | 
						|
    return m_start_of_statement_svp;
 | 
						|
  }
 | 
						|
 | 
						|
  inline ulong get_timeout() const
 | 
						|
  {
 | 
						|
    return m_timeout;
 | 
						|
  }
 | 
						|
 | 
						|
  uint get_flags() const { return m_flags; }
 | 
						|
private:
 | 
						|
  /**
 | 
						|
    For OT_DISCOVER and OT_REPAIR actions, the table list element for
 | 
						|
    the table which definition should be re-discovered or which
 | 
						|
    should be repaired.
 | 
						|
  */
 | 
						|
  TABLE_LIST *m_failed_table;
 | 
						|
  MDL_ticket *m_start_of_statement_svp;
 | 
						|
  /**
 | 
						|
    Lock timeout in seconds. Initialized to LONG_TIMEOUT when opening system
 | 
						|
    tables or to the "lock_wait_timeout" system variable for regular tables.
 | 
						|
  */
 | 
						|
  ulong m_timeout;
 | 
						|
  /* open_table() flags. */
 | 
						|
  uint m_flags;
 | 
						|
  /** Back off action. */
 | 
						|
  enum enum_open_table_action m_action;
 | 
						|
  /**
 | 
						|
    Whether we had any locks when this context was created.
 | 
						|
    If we did, they are from the previous statement of a transaction,
 | 
						|
    and we can't safely do back-off (and release them).
 | 
						|
  */
 | 
						|
  bool m_has_locks;
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
/**
 | 
						|
  This internal handler is used to trap ER_NO_SUCH_TABLE.
 | 
						|
*/
 | 
						|
 | 
						|
class No_such_table_error_handler : public Internal_error_handler
 | 
						|
{
 | 
						|
public:
 | 
						|
  No_such_table_error_handler()
 | 
						|
    : m_handled_errors(0), m_unhandled_errors(0)
 | 
						|
  {}
 | 
						|
 | 
						|
  bool handle_condition(THD *thd,
 | 
						|
                        uint sql_errno,
 | 
						|
                        const char* sqlstate,
 | 
						|
                        MYSQL_ERROR::enum_warning_level level,
 | 
						|
                        const char* msg,
 | 
						|
                        MYSQL_ERROR ** cond_hdl);
 | 
						|
 | 
						|
  /**
 | 
						|
    Returns TRUE if one or more ER_NO_SUCH_TABLE errors have been
 | 
						|
    trapped and no other errors have been seen. FALSE otherwise.
 | 
						|
  */
 | 
						|
  bool safely_trapped_errors();
 | 
						|
 | 
						|
private:
 | 
						|
  int m_handled_errors;
 | 
						|
  int m_unhandled_errors;
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
#endif /* SQL_BASE_INCLUDED */
 |