From 3fa2673f19e00245258bad1ca333a29c01540f99 Mon Sep 17 00:00:00 2001 From: Sergey Glukhov <Sergey.Glukhov@sun.com> Date: Thu, 13 Nov 2008 16:09:11 +0400 Subject: [PATCH] Bug#39955 SELECT on INFORMATION_SCHEMA.GLOBAL_VARIABLES takes too long VARIABLE_VALUE field is decreased to 1024 symbols. (affected I_S tables: GLOBAL_VARIABLES, SESSION_VARIABLES, GLOBAL_STATUS, SESSION_STATUS). The only variable which can be longer than 1024 is init_connect. The variable will be truncated with warning. Additional fix: Added where condition filter which speed up queries which have where condition with expressions which use VARIABLE_NAME field. --- mysql-test/r/information_schema.result | 47 ++++++++++++++++++ mysql-test/r/show_check.result | 6 +-- .../suite/funcs_1/r/is_columns_is.result | 16 +++--- mysql-test/t/information_schema.test | 27 ++++++++++ sql/sql_show.cc | 49 ++++++++++++------- 5 files changed, 116 insertions(+), 29 deletions(-) diff --git a/mysql-test/r/information_schema.result b/mysql-test/r/information_schema.result index 8f4caa3d6d1..0ed501252f6 100644 --- a/mysql-test/r/information_schema.result +++ b/mysql-test/r/information_schema.result @@ -1651,4 +1651,51 @@ id select_type table type possible_keys key key_len ref rows Extra explain select count(*) from information_schema.views; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE views ALL NULL NULL NULL NULL NULL Open_frm_only; Scanned all databases +set global init_connect="drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;"; +select * from information_schema.global_variables where variable_name='init_connect'; +VARIABLE_NAME VARIABLE_VALUE +INIT_CONNECT drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists t1; +drop table if exists t1;drop table if exists +Warnings: +Warning 1265 Data truncated for column 'VARIABLE_VALUE' at row 1 +set global init_connect=""; End of 5.1 tests. diff --git a/mysql-test/r/show_check.result b/mysql-test/r/show_check.result index ddc08dca7bb..d054e5cdc05 100644 --- a/mysql-test/r/show_check.result +++ b/mysql-test/r/show_check.result @@ -100,19 +100,19 @@ drop table t1; show variables like "wait_timeout%"; Catalog Database Table Table_alias Column Column_alias Type Length Max length Is_null Flags Decimals Charsetnr def VARIABLES VARIABLE_NAME Variable_name 253 64 12 N 1 0 8 -def VARIABLES VARIABLE_VALUE Value 253 20480 5 Y 0 0 8 +def VARIABLES VARIABLE_VALUE Value 253 1024 5 Y 0 0 8 Variable_name Value wait_timeout 28800 show variables like "WAIT_timeout%"; Catalog Database Table Table_alias Column Column_alias Type Length Max length Is_null Flags Decimals Charsetnr def VARIABLES VARIABLE_NAME Variable_name 253 64 12 N 1 0 8 -def VARIABLES VARIABLE_VALUE Value 253 20480 5 Y 0 0 8 +def VARIABLES VARIABLE_VALUE Value 253 1024 5 Y 0 0 8 Variable_name Value wait_timeout 28800 show variables like "this_doesn't_exists%"; Catalog Database Table Table_alias Column Column_alias Type Length Max length Is_null Flags Decimals Charsetnr def VARIABLES VARIABLE_NAME Variable_name 253 64 0 N 1 0 8 -def VARIABLES VARIABLE_VALUE Value 253 20480 0 Y 0 0 8 +def VARIABLES VARIABLE_VALUE Value 253 1024 0 Y 0 0 8 Variable_name Value show table status from test like "this_doesn't_exists%"; Catalog Database Table Table_alias Column Column_alias Type Length Max length Is_null Flags Decimals Charsetnr diff --git a/mysql-test/suite/funcs_1/r/is_columns_is.result b/mysql-test/suite/funcs_1/r/is_columns_is.result index 7a2257713d2..15466887ecc 100644 --- a/mysql-test/suite/funcs_1/r/is_columns_is.result +++ b/mysql-test/suite/funcs_1/r/is_columns_is.result @@ -110,9 +110,9 @@ NULL information_schema FILES UPDATE_COUNT 13 NULL YES bigint NULL NULL 19 0 NUL NULL information_schema FILES UPDATE_TIME 34 NULL YES datetime NULL NULL NULL NULL NULL NULL datetime select NULL information_schema FILES VERSION 25 NULL YES bigint NULL NULL 19 0 NULL NULL bigint(21) unsigned select NULL information_schema GLOBAL_STATUS VARIABLE_NAME 1 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select -NULL information_schema GLOBAL_STATUS VARIABLE_VALUE 2 NULL YES varchar 20480 61440 NULL NULL utf8 utf8_general_ci varchar(20480) select +NULL information_schema GLOBAL_STATUS VARIABLE_VALUE 2 NULL YES varchar 1024 3072 NULL NULL utf8 utf8_general_ci varchar(1024) select NULL information_schema GLOBAL_VARIABLES VARIABLE_NAME 1 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select -NULL information_schema GLOBAL_VARIABLES VARIABLE_VALUE 2 NULL YES varchar 20480 61440 NULL NULL utf8 utf8_general_ci varchar(20480) select +NULL information_schema GLOBAL_VARIABLES VARIABLE_VALUE 2 NULL YES varchar 1024 3072 NULL NULL utf8 utf8_general_ci varchar(1024) select NULL information_schema KEY_COLUMN_USAGE COLUMN_NAME 7 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select NULL information_schema KEY_COLUMN_USAGE CONSTRAINT_CATALOG 1 NULL YES varchar 512 1536 NULL NULL utf8 utf8_general_ci varchar(512) select NULL information_schema KEY_COLUMN_USAGE CONSTRAINT_NAME 3 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select @@ -213,9 +213,9 @@ NULL information_schema SCHEMA_PRIVILEGES PRIVILEGE_TYPE 4 NO varchar 64 192 NU NULL information_schema SCHEMA_PRIVILEGES TABLE_CATALOG 2 NULL YES varchar 512 1536 NULL NULL utf8 utf8_general_ci varchar(512) select NULL information_schema SCHEMA_PRIVILEGES TABLE_SCHEMA 3 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select NULL information_schema SESSION_STATUS VARIABLE_NAME 1 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select -NULL information_schema SESSION_STATUS VARIABLE_VALUE 2 NULL YES varchar 20480 61440 NULL NULL utf8 utf8_general_ci varchar(20480) select +NULL information_schema SESSION_STATUS VARIABLE_VALUE 2 NULL YES varchar 1024 3072 NULL NULL utf8 utf8_general_ci varchar(1024) select NULL information_schema SESSION_VARIABLES VARIABLE_NAME 1 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select -NULL information_schema SESSION_VARIABLES VARIABLE_VALUE 2 NULL YES varchar 20480 61440 NULL NULL utf8 utf8_general_ci varchar(20480) select +NULL information_schema SESSION_VARIABLES VARIABLE_VALUE 2 NULL YES varchar 1024 3072 NULL NULL utf8 utf8_general_ci varchar(1024) select NULL information_schema STATISTICS CARDINALITY 10 NULL YES bigint NULL NULL 19 0 NULL NULL bigint(21) select NULL information_schema STATISTICS COLLATION 9 NULL YES varchar 1 3 NULL NULL utf8 utf8_general_ci varchar(1) select NULL information_schema STATISTICS COLUMN_NAME 8 NO varchar 64 192 NULL NULL utf8 utf8_general_ci varchar(64) select @@ -464,9 +464,9 @@ NULL information_schema FILES CHECKSUM bigint NULL NULL NULL NULL bigint(21) uns 3.0000 information_schema FILES STATUS varchar 20 60 utf8 utf8_general_ci varchar(20) 3.0000 information_schema FILES EXTRA varchar 255 765 utf8 utf8_general_ci varchar(255) 3.0000 information_schema GLOBAL_STATUS VARIABLE_NAME varchar 64 192 utf8 utf8_general_ci varchar(64) -3.0000 information_schema GLOBAL_STATUS VARIABLE_VALUE varchar 20480 61440 utf8 utf8_general_ci varchar(20480) +3.0000 information_schema GLOBAL_STATUS VARIABLE_VALUE varchar 1024 3072 utf8 utf8_general_ci varchar(1024) 3.0000 information_schema GLOBAL_VARIABLES VARIABLE_NAME varchar 64 192 utf8 utf8_general_ci varchar(64) -3.0000 information_schema GLOBAL_VARIABLES VARIABLE_VALUE varchar 20480 61440 utf8 utf8_general_ci varchar(20480) +3.0000 information_schema GLOBAL_VARIABLES VARIABLE_VALUE varchar 1024 3072 utf8 utf8_general_ci varchar(1024) 3.0000 information_schema KEY_COLUMN_USAGE CONSTRAINT_CATALOG varchar 512 1536 utf8 utf8_general_ci varchar(512) 3.0000 information_schema KEY_COLUMN_USAGE CONSTRAINT_SCHEMA varchar 64 192 utf8 utf8_general_ci varchar(64) 3.0000 information_schema KEY_COLUMN_USAGE CONSTRAINT_NAME varchar 64 192 utf8 utf8_general_ci varchar(64) @@ -567,9 +567,9 @@ NULL information_schema ROUTINES LAST_ALTERED datetime NULL NULL NULL NULL datet 3.0000 information_schema SCHEMA_PRIVILEGES PRIVILEGE_TYPE varchar 64 192 utf8 utf8_general_ci varchar(64) 3.0000 information_schema SCHEMA_PRIVILEGES IS_GRANTABLE varchar 3 9 utf8 utf8_general_ci varchar(3) 3.0000 information_schema SESSION_STATUS VARIABLE_NAME varchar 64 192 utf8 utf8_general_ci varchar(64) -3.0000 information_schema SESSION_STATUS VARIABLE_VALUE varchar 20480 61440 utf8 utf8_general_ci varchar(20480) +3.0000 information_schema SESSION_STATUS VARIABLE_VALUE varchar 1024 3072 utf8 utf8_general_ci varchar(1024) 3.0000 information_schema SESSION_VARIABLES VARIABLE_NAME varchar 64 192 utf8 utf8_general_ci varchar(64) -3.0000 information_schema SESSION_VARIABLES VARIABLE_VALUE varchar 20480 61440 utf8 utf8_general_ci varchar(20480) +3.0000 information_schema SESSION_VARIABLES VARIABLE_VALUE varchar 1024 3072 utf8 utf8_general_ci varchar(1024) 3.0000 information_schema STATISTICS TABLE_CATALOG varchar 512 1536 utf8 utf8_general_ci varchar(512) 3.0000 information_schema STATISTICS TABLE_SCHEMA varchar 64 192 utf8 utf8_general_ci varchar(64) 3.0000 information_schema STATISTICS TABLE_NAME varchar 64 192 utf8 utf8_general_ci varchar(64) diff --git a/mysql-test/t/information_schema.test b/mysql-test/t/information_schema.test index 4027293da66..667a9279e84 100644 --- a/mysql-test/t/information_schema.test +++ b/mysql-test/t/information_schema.test @@ -1346,4 +1346,31 @@ explain select count(*) from information_schema.tables; explain select count(*) from information_schema.columns; explain select count(*) from information_schema.views; +# +# Bug#39955 SELECT on INFORMATION_SCHEMA.GLOBAL_VARIABLES takes too long +# +set global init_connect="drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;\ +drop table if exists t1;drop table if exists t1;"; +select * from information_schema.global_variables where variable_name='init_connect'; +set global init_connect=""; + --echo End of 5.1 tests. diff --git a/sql/sql_show.cc b/sql/sql_show.cc index 3e788db13d2..0d51c7457c3 100644 --- a/sql/sql_show.cc +++ b/sql/sql_show.cc @@ -83,6 +83,7 @@ static void store_key_options(THD *thd, String *packet, TABLE *table, static void append_algorithm(TABLE_LIST *table, String *buff); +static COND * make_cond_for_info_schema(COND *cond, TABLE_LIST *table); /*************************************************************************** ** List all table types supported @@ -2072,7 +2073,8 @@ static bool show_status_array(THD *thd, const char *wild, enum enum_var_type value_type, struct system_status_var *status_var, const char *prefix, TABLE *table, - bool ucase_names) + bool ucase_names, + COND *cond) { MY_ALIGNED_BYTE_ARRAY(buff_data, SHOW_VAR_FUNC_BUFF_SIZE, long); char * const buff= (char *) &buff_data; @@ -2082,8 +2084,12 @@ static bool show_status_array(THD *thd, const char *wild, int len; LEX_STRING null_lex_str; SHOW_VAR tmp, *var; + COND *partial_cond= 0; + enum_check_fields save_count_cuted_fields= thd->count_cuted_fields; + bool res= FALSE; DBUG_ENTER("show_status_array"); + thd->count_cuted_fields= CHECK_FIELD_WARN; null_lex_str.str= 0; // For sys_var->value_ptr() null_lex_str.length= 0; @@ -2091,6 +2097,7 @@ static bool show_status_array(THD *thd, const char *wild, if (*prefix) *prefix_end++= '_'; len=name_buffer + sizeof(name_buffer) - prefix_end; + partial_cond= make_cond_for_info_schema(cond, table->pos_in_table_list); for (; variables->name; variables++) { @@ -2099,6 +2106,9 @@ static bool show_status_array(THD *thd, const char *wild, if (ucase_names) make_upper(name_buffer); + restore_record(table, s->default_values); + table->field[0]->store(name_buffer, strlen(name_buffer), + system_charset_info); /* if var->type is SHOW_FUNC, call the function. Repeat as necessary, if new var is again SHOW_FUNC @@ -2110,12 +2120,13 @@ static bool show_status_array(THD *thd, const char *wild, if (show_type == SHOW_ARRAY) { show_status_array(thd, wild, (SHOW_VAR *) var->value, value_type, - status_var, name_buffer, table, ucase_names); + status_var, name_buffer, table, ucase_names, partial_cond); } else { if (!(wild && wild[0] && wild_case_compare(system_charset_info, - name_buffer, wild))) + name_buffer, wild)) && + (!partial_cond || partial_cond->val_int())) { char *value=var->value; const char *pos, *end; // We assign a lot of const's @@ -2202,21 +2213,23 @@ static bool show_status_array(THD *thd, const char *wild, DBUG_ASSERT(0); break; } - restore_record(table, s->default_values); - table->field[0]->store(name_buffer, strlen(name_buffer), - system_charset_info); table->field[1]->store(pos, (uint32) (end - pos), system_charset_info); + thd->count_cuted_fields= CHECK_FIELD_IGNORE; table->field[1]->set_notnull(); pthread_mutex_unlock(&LOCK_global_system_variables); if (schema_table_store_record(thd, table)) - DBUG_RETURN(TRUE); + { + res= TRUE; + goto end; + } } } } - - DBUG_RETURN(FALSE); +end: + thd->count_cuted_fields= save_count_cuted_fields; + DBUG_RETURN(res); } @@ -5244,7 +5257,7 @@ int fill_variables(THD *thd, TABLE_LIST *tables, COND *cond) rw_rdlock(&LOCK_system_variables_hash); res= show_status_array(thd, wild, enumerate_sys_vars(thd, sorted_vars), - option_type, NULL, "", tables->table, upper_case_names); + option_type, NULL, "", tables->table, upper_case_names, cond); rw_unlock(&LOCK_system_variables_hash); DBUG_RETURN(res); } @@ -5287,7 +5300,7 @@ int fill_status(THD *thd, TABLE_LIST *tables, COND *cond) res= show_status_array(thd, wild, (SHOW_VAR *)all_status_vars.buffer, option_type, tmp1, "", tables->table, - upper_case_names); + upper_case_names, cond); pthread_mutex_unlock(&LOCK_status); DBUG_RETURN(res); } @@ -6456,7 +6469,7 @@ ST_FIELD_INFO variables_fields_info[]= { {"VARIABLE_NAME", 64, MYSQL_TYPE_STRING, 0, 0, "Variable_name", SKIP_OPEN_TABLE}, - {"VARIABLE_VALUE", 20480, MYSQL_TYPE_STRING, 0, 1, "Value", SKIP_OPEN_TABLE}, + {"VARIABLE_VALUE", 1024, MYSQL_TYPE_STRING, 0, 1, "Value", SKIP_OPEN_TABLE}, {0, 0, MYSQL_TYPE_STRING, 0, 0, 0, SKIP_OPEN_TABLE} }; @@ -6615,9 +6628,9 @@ ST_SCHEMA_TABLE schema_tables[]= {"FILES", files_fields_info, create_schema_table, fill_schema_files, 0, 0, -1, -1, 0, 0}, {"GLOBAL_STATUS", variables_fields_info, create_schema_table, - fill_status, make_old_format, 0, -1, -1, 0, 0}, + fill_status, make_old_format, 0, 0, -1, 0, 0}, {"GLOBAL_VARIABLES", variables_fields_info, create_schema_table, - fill_variables, make_old_format, 0, -1, -1, 0, 0}, + fill_variables, make_old_format, 0, 0, -1, 0, 0}, {"KEY_COLUMN_USAGE", key_column_usage_fields_info, create_schema_table, get_all_tables, 0, get_schema_key_column_usage_record, 4, 5, 0, OPEN_TABLE_ONLY}, @@ -6642,14 +6655,14 @@ ST_SCHEMA_TABLE schema_tables[]= {"SCHEMA_PRIVILEGES", schema_privileges_fields_info, create_schema_table, fill_schema_schema_privileges, 0, 0, -1, -1, 0, 0}, {"SESSION_STATUS", variables_fields_info, create_schema_table, - fill_status, make_old_format, 0, -1, -1, 0, 0}, + fill_status, make_old_format, 0, 0, -1, 0, 0}, {"SESSION_VARIABLES", variables_fields_info, create_schema_table, - fill_variables, make_old_format, 0, -1, -1, 0, 0}, + fill_variables, make_old_format, 0, 0, -1, 0, 0}, {"STATISTICS", stat_fields_info, create_schema_table, get_all_tables, make_old_format, get_schema_stat_record, 1, 2, 0, OPEN_TABLE_ONLY|OPTIMIZE_I_S_TABLE}, {"STATUS", variables_fields_info, create_schema_table, fill_status, - make_old_format, 0, -1, -1, 1, 0}, + make_old_format, 0, 0, -1, 1, 0}, {"TABLES", tables_fields_info, create_schema_table, get_all_tables, make_old_format, get_schema_tables_record, 1, 2, 0, OPTIMIZE_I_S_TABLE}, @@ -6665,7 +6678,7 @@ ST_SCHEMA_TABLE schema_tables[]= {"USER_PRIVILEGES", user_privileges_fields_info, create_schema_table, fill_schema_user_privileges, 0, 0, -1, -1, 0, 0}, {"VARIABLES", variables_fields_info, create_schema_table, fill_variables, - make_old_format, 0, -1, -1, 1, 0}, + make_old_format, 0, 0, -1, 1, 0}, {"VIEWS", view_fields_info, create_schema_table, get_all_tables, 0, get_schema_views_record, 1, 2, 0, OPEN_VIEW_ONLY|OPTIMIZE_I_S_TABLE}, -- 2.30.9