DROP TABLE IF EXISTS t0,t1,t2,t3,t4,t5; DROP VIEW IF EXISTS v1; show variables where variable_name like "skip_show_database"; Variable_name Value skip_show_database OFF grant select, update, execute on test.* to mysqltest_2@localhost; grant select, update on test.* to mysqltest_1@localhost; create user mysqltest_3@localhost; create user mysqltest_3; select * from information_schema.SCHEMATA where schema_name > 'm'; CATALOG_NAME SCHEMA_NAME DEFAULT_CHARACTER_SET_NAME DEFAULT_COLLATION_NAME SQL_PATH NULL mtr latin1 latin1_swedish_ci NULL NULL mysql latin1 latin1_swedish_ci NULL NULL test latin1 latin1_swedish_ci NULL select schema_name from information_schema.schemata; schema_name information_schema mtr mysql test show databases like 't%'; Database (t%) test show databases; Database information_schema mtr mysql test show databases where `database` = 't%'; Database create database mysqltest; create table mysqltest.t1(a int, b VARCHAR(30), KEY string_data (b)); create table test.t2(a int); create table t3(a int, KEY a_data (a)); create table mysqltest.t4(a int); create table t5 (id int auto_increment primary key); insert into t5 values (10); create view v1 (c) as SELECT table_name FROM information_schema.TABLES WHERE table_schema IN ('mysql', 'INFORMATION_SCHEMA', 'test', 'mysqltest') AND table_name<>'ndb_binlog_index' AND table_name<>'ndb_apply_status'; select * from v1; c CHARACTER_SETS COLLATIONS COLLATION_CHARACTER_SET_APPLICABILITY COLUMNS COLUMN_PRIVILEGES ENGINES EVENTS FILES GLOBAL_STATUS GLOBAL_VARIABLES KEY_COLUMN_USAGE PARTITIONS PLUGINS PROCESSLIST PROFILING REFERENTIAL_CONSTRAINTS ROUTINES SCHEMATA SCHEMA_PRIVILEGES SESSION_STATUS SESSION_VARIABLES STATISTICS TABLES TABLE_CONSTRAINTS TABLE_PRIVILEGES TRIGGERS USER_PRIVILEGES VIEWS columns_priv db event func general_log help_category help_keyword help_relation help_topic host plugin proc procs_priv servers slow_log tables_priv time_zone time_zone_leap_second time_zone_name time_zone_transition time_zone_transition_type user t1 t4 t2 t3 t5 v1 select c,table_name from v1 inner join information_schema.TABLES v2 on (v1.c=v2.table_name) where v1.c like "t%"; c table_name TABLES TABLES TABLE_CONSTRAINTS TABLE_CONSTRAINTS TABLE_PRIVILEGES TABLE_PRIVILEGES TRIGGERS TRIGGERS tables_priv tables_priv time_zone time_zone time_zone_leap_second time_zone_leap_second time_zone_name time_zone_name time_zone_transition time_zone_transition time_zone_transition_type time_zone_transition_type t1 t1 t4 t4 t2 t2 t3 t3 t5 t5 select c,table_name from v1 left join information_schema.TABLES v2 on (v1.c=v2.table_name) where v1.c like "t%"; c table_name TABLES TABLES TABLE_CONSTRAINTS TABLE_CONSTRAINTS TABLE_PRIVILEGES TABLE_PRIVILEGES TRIGGERS TRIGGERS tables_priv tables_priv time_zone time_zone time_zone_leap_second time_zone_leap_second time_zone_name time_zone_name time_zone_transition time_zone_transition time_zone_transition_type time_zone_transition_type t1 t1 t4 t4 t2 t2 t3 t3 t5 t5 select c, v2.table_name from v1 right join information_schema.TABLES v2 on (v1.c=v2.table_name) where v1.c like "t%"; c table_name TABLES TABLES TABLE_CONSTRAINTS TABLE_CONSTRAINTS TABLE_PRIVILEGES TABLE_PRIVILEGES TRIGGERS TRIGGERS tables_priv tables_priv time_zone time_zone time_zone_leap_second time_zone_leap_second time_zone_name time_zone_name time_zone_transition time_zone_transition time_zone_transition_type time_zone_transition_type t1 t1 t4 t4 t2 t2 t3 t3 t5 t5 select table_name from information_schema.TABLES where table_schema = "mysqltest" and table_name like "t%"; table_name t1 t4 select * from information_schema.STATISTICS where TABLE_SCHEMA = "mysqltest"; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME NON_UNIQUE INDEX_SCHEMA INDEX_NAME SEQ_IN_INDEX COLUMN_NAME COLLATION CARDINALITY SUB_PART PACKED NULLABLE INDEX_TYPE COMMENT NULL mysqltest t1 1 mysqltest string_data 1 b A NULL NULL NULL YES BTREE show keys from t3 where Key_name = "a_data"; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment t3 1 a_data 1 a A NULL NULL NULL YES BTREE show tables like 't%'; Tables_in_test (t%) t2 t3 t5 show table status; Name Engine Version Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Collation Checksum Create_options Comment t2 MyISAM 10 Fixed 0 0 0 # 1024 0 NULL # # NULL latin1_swedish_ci NULL t3 MyISAM 10 Fixed 0 0 0 # 1024 0 NULL # # NULL latin1_swedish_ci NULL t5 MyISAM 10 Fixed 1 7 7 # 2048 0 11 # # NULL latin1_swedish_ci NULL v1 NULL NULL NULL NULL NULL NULL # NULL NULL NULL # # NULL NULL NULL NULL VIEW show full columns from t3 like "a%"; Field Type Collation Null Key Default Extra Privileges Comment a int(11) NULL YES MUL NULL select,insert,update,references show full columns from mysql.db like "Insert%"; Field Type Collation Null Key Default Extra Privileges Comment Insert_priv enum('N','Y') utf8_general_ci NO N select,insert,update,references show full columns from v1; Field Type Collation Null Key Default Extra Privileges Comment c varchar(64) utf8_general_ci NO select,insert,update,references select * from information_schema.COLUMNS where table_name="t1" and column_name= "a"; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE COLUMN_KEY EXTRA PRIVILEGES COLUMN_COMMENT STORAGE FORMAT NULL mysqltest t1 a 1 NULL YES int NULL NULL 10 0 NULL NULL int(11) select,insert,update,references Default Default show columns from mysqltest.t1 where field like "%a%"; Field Type Null Key Default Extra a int(11) YES NULL create view mysqltest.v1 (c) as select a from mysqltest.t1; grant select (a) on mysqltest.t1 to mysqltest_2@localhost; grant select on mysqltest.v1 to mysqltest_3; select table_name, column_name, privileges from information_schema.columns where table_schema = 'mysqltest' and table_name = 't1'; table_name column_name privileges t1 a select show columns from mysqltest.t1; Field Type Null Key Default Extra a int(11) YES NULL select table_name, column_name, privileges from information_schema.columns where table_schema = 'mysqltest' and table_name = 'v1'; table_name column_name privileges v1 c select explain select * from v1; ERROR HY000: EXPLAIN/SHOW can not be issued; lacking privileges for underlying table drop view v1, mysqltest.v1; drop tables mysqltest.t4, mysqltest.t1, t2, t3, t5; drop database mysqltest; select * from information_schema.CHARACTER_SETS where CHARACTER_SET_NAME like 'latin1%'; CHARACTER_SET_NAME DEFAULT_COLLATE_NAME DESCRIPTION MAXLEN latin1 latin1_swedish_ci cp1252 West European 1 SHOW CHARACTER SET LIKE 'latin1%'; Charset Description Default collation Maxlen latin1 cp1252 West European latin1_swedish_ci 1 SHOW CHARACTER SET WHERE charset like 'latin1%'; Charset Description Default collation Maxlen latin1 cp1252 West European latin1_swedish_ci 1 select * from information_schema.COLLATIONS where COLLATION_NAME like 'latin1%'; COLLATION_NAME CHARACTER_SET_NAME ID IS_DEFAULT IS_COMPILED SORTLEN latin1_german1_ci latin1 5 # 1 latin1_swedish_ci latin1 8 Yes # 1 latin1_danish_ci latin1 15 # 1 latin1_german2_ci latin1 31 # 2 latin1_bin latin1 47 # 1 latin1_general_ci latin1 48 # 1 latin1_general_cs latin1 49 # 1 latin1_spanish_ci latin1 94 # 1 SHOW COLLATION LIKE 'latin1%'; Collation Charset Id Default Compiled Sortlen latin1_german1_ci latin1 5 # 1 latin1_swedish_ci latin1 8 Yes # 1 latin1_danish_ci latin1 15 # 1 latin1_german2_ci latin1 31 # 2 latin1_bin latin1 47 # 1 latin1_general_ci latin1 48 # 1 latin1_general_cs latin1 49 # 1 latin1_spanish_ci latin1 94 # 1 SHOW COLLATION WHERE collation like 'latin1%'; Collation Charset Id Default Compiled Sortlen latin1_german1_ci latin1 5 # 1 latin1_swedish_ci latin1 8 Yes # 1 latin1_danish_ci latin1 15 # 1 latin1_german2_ci latin1 31 # 2 latin1_bin latin1 47 # 1 latin1_general_ci latin1 48 # 1 latin1_general_cs latin1 49 # 1 latin1_spanish_ci latin1 94 # 1 select * from information_schema.COLLATION_CHARACTER_SET_APPLICABILITY where COLLATION_NAME like 'latin1%'; COLLATION_NAME CHARACTER_SET_NAME latin1_german1_ci latin1 latin1_swedish_ci latin1 latin1_danish_ci latin1 latin1_german2_ci latin1 latin1_bin latin1 latin1_general_ci latin1 latin1_general_cs latin1 latin1_spanish_ci latin1 drop procedure if exists sel2; drop function if exists sub1; drop function if exists sub2; create function sub1(i int) returns int return i+1; create procedure sel2() begin select * from t1; select * from t2; end| select parameter_style, sql_data_access, dtd_identifier from information_schema.routines where routine_schema='test'; parameter_style sql_data_access dtd_identifier SQL CONTAINS SQL NULL SQL CONTAINS SQL int(11) show procedure status where db='test'; Db Name Type Definer Modified Created Security_type Comment character_set_client collation_connection Database Collation test sel2 PROCEDURE root@localhost # # DEFINER latin1 latin1_swedish_ci latin1_swedish_ci show function status where db='test'; Db Name Type Definer Modified Created Security_type Comment character_set_client collation_connection Database Collation test sub1 FUNCTION root@localhost # # DEFINER latin1 latin1_swedish_ci latin1_swedish_ci select a.ROUTINE_NAME from information_schema.ROUTINES a, information_schema.SCHEMATA b where a.ROUTINE_SCHEMA = b.SCHEMA_NAME AND b.SCHEMA_NAME='test'; ROUTINE_NAME sel2 sub1 explain select a.ROUTINE_NAME from information_schema.ROUTINES a, information_schema.SCHEMATA b where a.ROUTINE_SCHEMA = b.SCHEMA_NAME; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE # ALL NULL NULL NULL NULL NULL 1 SIMPLE # ALL NULL NULL NULL NULL NULL Using where; Using join buffer select a.ROUTINE_NAME, b.name from information_schema.ROUTINES a, mysql.proc b where a.ROUTINE_NAME = convert(b.name using utf8) AND a.ROUTINE_SCHEMA='test' order by 1; ROUTINE_NAME name sel2 sel2 sub1 sub1 select count(*) from information_schema.ROUTINES where routine_schema='test'; count(*) 2 create view v1 as select routine_schema, routine_name from information_schema.routines where routine_schema='test' order by routine_schema, routine_name; select * from v1; routine_schema routine_name test sel2 test sub1 drop view v1; select ROUTINE_NAME, ROUTINE_DEFINITION from information_schema.ROUTINES; ROUTINE_NAME ROUTINE_DEFINITION show create function sub1; ERROR 42000: FUNCTION sub1 does not exist select ROUTINE_NAME, ROUTINE_DEFINITION from information_schema.ROUTINES; ROUTINE_NAME ROUTINE_DEFINITION sel2 NULL sub1 NULL grant all privileges on test.* to mysqltest_1@localhost; select ROUTINE_NAME, ROUTINE_DEFINITION from information_schema.ROUTINES; ROUTINE_NAME ROUTINE_DEFINITION sel2 NULL sub1 NULL create function sub2(i int) returns int return i+1; select ROUTINE_NAME, ROUTINE_DEFINITION from information_schema.ROUTINES; ROUTINE_NAME ROUTINE_DEFINITION sel2 NULL sub1 NULL sub2 return i+1 show create procedure sel2; Procedure sql_mode Create Procedure character_set_client collation_connection Database Collation sel2 NULL latin1 latin1_swedish_ci latin1_swedish_ci show create function sub1; Function sql_mode Create Function character_set_client collation_connection Database Collation sub1 NULL latin1 latin1_swedish_ci latin1_swedish_ci show create function sub2; Function sql_mode Create Function character_set_client collation_connection Database Collation sub2 CREATE DEFINER=`mysqltest_1`@`localhost` FUNCTION `sub2`(i int) RETURNS int(11) return i+1 latin1 latin1_swedish_ci latin1_swedish_ci show function status like "sub2"; Db Name Type Definer Modified Created Security_type Comment character_set_client collation_connection Database Collation test sub2 FUNCTION mysqltest_1@localhost # # DEFINER latin1 latin1_swedish_ci latin1_swedish_ci drop function sub2; show create procedure sel2; Procedure sql_mode Create Procedure character_set_client collation_connection Database Collation sel2 CREATE DEFINER=`root`@`localhost` PROCEDURE `sel2`() begin select * from t1; select * from t2; end latin1 latin1_swedish_ci latin1_swedish_ci create view v0 (c) as select schema_name from information_schema.schemata; select * from v0; c information_schema mtr mysql test explain select * from v0; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE # ALL NULL NULL NULL NULL NULL create view v1 (c) as select table_name from information_schema.tables where table_name="v1"; select * from v1; c v1 create view v2 (c) as select column_name from information_schema.columns where table_name="v2"; select * from v2; c c create view v3 (c) as select CHARACTER_SET_NAME from information_schema.character_sets where CHARACTER_SET_NAME like "latin1%"; select * from v3; c latin1 create view v4 (c) as select COLLATION_NAME from information_schema.collations where COLLATION_NAME like "latin1%"; select * from v4; c latin1_german1_ci latin1_swedish_ci latin1_danish_ci latin1_german2_ci latin1_bin latin1_general_ci latin1_general_cs latin1_spanish_ci show keys from v4; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment select * from information_schema.views where TABLE_NAME like "v%"; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME VIEW_DEFINITION CHECK_OPTION IS_UPDATABLE DEFINER SECURITY_TYPE CHARACTER_SET_CLIENT COLLATION_CONNECTION NULL test v0 select `schemata`.`SCHEMA_NAME` AS `c` from `information_schema`.`schemata` NONE NO root@localhost DEFINER latin1 latin1_swedish_ci NULL test v1 select `tables`.`TABLE_NAME` AS `c` from `information_schema`.`tables` where (`tables`.`TABLE_NAME` = 'v1') NONE NO root@localhost DEFINER latin1 latin1_swedish_ci NULL test v2 select `columns`.`COLUMN_NAME` AS `c` from `information_schema`.`columns` where (`columns`.`TABLE_NAME` = 'v2') NONE NO root@localhost DEFINER latin1 latin1_swedish_ci NULL test v3 select `character_sets`.`CHARACTER_SET_NAME` AS `c` from `information_schema`.`character_sets` where (`character_sets`.`CHARACTER_SET_NAME` like 'latin1%') NONE NO root@localhost DEFINER latin1 latin1_swedish_ci NULL test v4 select `collations`.`COLLATION_NAME` AS `c` from `information_schema`.`collations` where (`collations`.`COLLATION_NAME` like 'latin1%') NONE NO root@localhost DEFINER latin1 latin1_swedish_ci drop view v0, v1, v2, v3, v4; create table t1 (a int); grant select,update,insert on t1 to mysqltest_1@localhost; grant select (a), update (a),insert(a), references(a) on t1 to mysqltest_1@localhost; grant all on test.* to mysqltest_1@localhost with grant option; select * from information_schema.USER_PRIVILEGES where grantee like '%mysqltest_1%'; GRANTEE TABLE_CATALOG PRIVILEGE_TYPE IS_GRANTABLE 'mysqltest_1'@'localhost' NULL USAGE NO select * from information_schema.SCHEMA_PRIVILEGES where grantee like '%mysqltest_1%'; GRANTEE TABLE_CATALOG TABLE_SCHEMA PRIVILEGE_TYPE IS_GRANTABLE 'mysqltest_1'@'localhost' NULL test SELECT YES 'mysqltest_1'@'localhost' NULL test INSERT YES 'mysqltest_1'@'localhost' NULL test UPDATE YES 'mysqltest_1'@'localhost' NULL test DELETE YES 'mysqltest_1'@'localhost' NULL test CREATE YES 'mysqltest_1'@'localhost' NULL test DROP YES 'mysqltest_1'@'localhost' NULL test REFERENCES YES 'mysqltest_1'@'localhost' NULL test INDEX YES 'mysqltest_1'@'localhost' NULL test ALTER YES 'mysqltest_1'@'localhost' NULL test CREATE TEMPORARY TABLES YES 'mysqltest_1'@'localhost' NULL test LOCK TABLES YES 'mysqltest_1'@'localhost' NULL test EXECUTE YES 'mysqltest_1'@'localhost' NULL test CREATE VIEW YES 'mysqltest_1'@'localhost' NULL test SHOW VIEW YES 'mysqltest_1'@'localhost' NULL test CREATE ROUTINE YES 'mysqltest_1'@'localhost' NULL test ALTER ROUTINE YES 'mysqltest_1'@'localhost' NULL test EVENT YES 'mysqltest_1'@'localhost' NULL test TRIGGER YES select * from information_schema.TABLE_PRIVILEGES where grantee like '%mysqltest_1%'; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PRIVILEGE_TYPE IS_GRANTABLE 'mysqltest_1'@'localhost' NULL test t1 SELECT NO 'mysqltest_1'@'localhost' NULL test t1 INSERT NO 'mysqltest_1'@'localhost' NULL test t1 UPDATE NO select * from information_schema.COLUMN_PRIVILEGES where grantee like '%mysqltest_1%'; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME PRIVILEGE_TYPE IS_GRANTABLE 'mysqltest_1'@'localhost' NULL test t1 a SELECT NO 'mysqltest_1'@'localhost' NULL test t1 a INSERT NO 'mysqltest_1'@'localhost' NULL test t1 a UPDATE NO 'mysqltest_1'@'localhost' NULL test t1 a REFERENCES NO delete from mysql.user where user like 'mysqltest%'; delete from mysql.db where user like 'mysqltest%'; delete from mysql.tables_priv where user like 'mysqltest%'; delete from mysql.columns_priv where user like 'mysqltest%'; flush privileges; drop table t1; create table t1 (a int null, primary key(a)); alter table t1 add constraint constraint_1 unique (a); alter table t1 add constraint unique key_1(a); alter table t1 add constraint constraint_2 unique key_2(a); show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` int(11) NOT NULL DEFAULT '0', PRIMARY KEY (`a`), UNIQUE KEY `constraint_1` (`a`), UNIQUE KEY `key_1` (`a`), UNIQUE KEY `key_2` (`a`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 select * from information_schema.TABLE_CONSTRAINTS where TABLE_SCHEMA= "test"; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_SCHEMA TABLE_NAME CONSTRAINT_TYPE NULL test PRIMARY test t1 PRIMARY KEY NULL test constraint_1 test t1 UNIQUE NULL test key_1 test t1 UNIQUE NULL test key_2 test t1 UNIQUE select * from information_schema.KEY_COLUMN_USAGE where TABLE_SCHEMA= "test"; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION POSITION_IN_UNIQUE_CONSTRAINT REFERENCED_TABLE_SCHEMA REFERENCED_TABLE_NAME REFERENCED_COLUMN_NAME NULL test PRIMARY NULL test t1 a 1 NULL NULL NULL NULL NULL test constraint_1 NULL test t1 a 1 NULL NULL NULL NULL NULL test key_1 NULL test t1 a 1 NULL NULL NULL NULL NULL test key_2 NULL test t1 a 1 NULL NULL NULL NULL select table_name from information_schema.TABLES where table_schema like "test%"; table_name t1 select table_name,column_name from information_schema.COLUMNS where table_schema like "test%"; table_name column_name t1 a select ROUTINE_NAME from information_schema.ROUTINES; ROUTINE_NAME sel2 sub1 delete from mysql.user where user='mysqltest_1'; drop table t1; drop procedure sel2; drop function sub1; create table t1(a int); create view v1 (c) as select a from t1 with check option; create view v2 (c) as select a from t1 WITH LOCAL CHECK OPTION; create view v3 (c) as select a from t1 WITH CASCADED CHECK OPTION; select * from information_schema.views; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME VIEW_DEFINITION CHECK_OPTION IS_UPDATABLE DEFINER SECURITY_TYPE CHARACTER_SET_CLIENT COLLATION_CONNECTION NULL test v1 select `test`.`t1`.`a` AS `c` from `test`.`t1` CASCADED YES root@localhost DEFINER latin1 latin1_swedish_ci NULL test v2 select `test`.`t1`.`a` AS `c` from `test`.`t1` LOCAL YES root@localhost DEFINER latin1 latin1_swedish_ci NULL test v3 select `test`.`t1`.`a` AS `c` from `test`.`t1` CASCADED YES root@localhost DEFINER latin1 latin1_swedish_ci grant select (a) on test.t1 to joe@localhost with grant option; select * from INFORMATION_SCHEMA.COLUMN_PRIVILEGES; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME PRIVILEGE_TYPE IS_GRANTABLE 'joe'@'localhost' NULL test t1 a SELECT YES select * from INFORMATION_SCHEMA.TABLE_PRIVILEGES; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PRIVILEGE_TYPE IS_GRANTABLE drop view v1, v2, v3; drop table t1; delete from mysql.user where user='joe'; delete from mysql.db where user='joe'; delete from mysql.tables_priv where user='joe'; delete from mysql.columns_priv where user='joe'; flush privileges; create table t1 (a int not null auto_increment,b int, primary key (a)); insert into t1 values (1,1),(NULL,3),(NULL,4); select AUTO_INCREMENT from information_schema.tables where table_name = 't1'; AUTO_INCREMENT 4 drop table t1; create table t1 (s1 int); insert into t1 values (0),(9),(0); select s1 from t1 where s1 in (select version from information_schema.tables) union select version from information_schema.tables; s1 10 drop table t1; SHOW CREATE TABLE INFORMATION_SCHEMA.character_sets; Table Create Table CHARACTER_SETS CREATE TEMPORARY TABLE `CHARACTER_SETS` ( `CHARACTER_SET_NAME` varchar(32) NOT NULL DEFAULT '', `DEFAULT_COLLATE_NAME` varchar(32) NOT NULL DEFAULT '', `DESCRIPTION` varchar(60) NOT NULL DEFAULT '', `MAXLEN` bigint(3) NOT NULL DEFAULT '0' ) ENGINE=MEMORY DEFAULT CHARSET=utf8 set names latin2; SHOW CREATE TABLE INFORMATION_SCHEMA.character_sets; Table Create Table CHARACTER_SETS CREATE TEMPORARY TABLE `CHARACTER_SETS` ( `CHARACTER_SET_NAME` varchar(32) NOT NULL DEFAULT '', `DEFAULT_COLLATE_NAME` varchar(32) NOT NULL DEFAULT '', `DESCRIPTION` varchar(60) NOT NULL DEFAULT '', `MAXLEN` bigint(3) NOT NULL DEFAULT '0' ) ENGINE=MEMORY DEFAULT CHARSET=utf8 set names latin1; create table t1 select * from information_schema.CHARACTER_SETS where CHARACTER_SET_NAME like "latin1"; select * from t1; CHARACTER_SET_NAME DEFAULT_COLLATE_NAME DESCRIPTION MAXLEN latin1 latin1_swedish_ci cp1252 West European 1 alter table t1 default character set utf8; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `CHARACTER_SET_NAME` varchar(32) NOT NULL DEFAULT '', `DEFAULT_COLLATE_NAME` varchar(32) NOT NULL DEFAULT '', `DESCRIPTION` varchar(60) NOT NULL DEFAULT '', `MAXLEN` bigint(3) NOT NULL DEFAULT '0' ) ENGINE=MyISAM DEFAULT CHARSET=utf8 drop table t1; create view v1 as select * from information_schema.TABLES; drop view v1; create table t1(a NUMERIC(5,3), b NUMERIC(5,1), c float(5,2), d NUMERIC(6,4), e float, f DECIMAL(6,3), g int(11), h DOUBLE(10,3), i DOUBLE); select COLUMN_NAME,COLUMN_TYPE, CHARACTER_MAXIMUM_LENGTH, CHARACTER_OCTET_LENGTH, NUMERIC_PRECISION, NUMERIC_SCALE from information_schema.columns where table_name= 't1'; COLUMN_NAME COLUMN_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE a decimal(5,3) NULL NULL 5 3 b decimal(5,1) NULL NULL 5 1 c float(5,2) NULL NULL 5 2 d decimal(6,4) NULL NULL 6 4 e float NULL NULL 12 NULL f decimal(6,3) NULL NULL 6 3 g int(11) NULL NULL 10 0 h double(10,3) NULL NULL 10 3 i double NULL NULL 22 NULL drop table t1; create table t115 as select table_name, column_name, column_type from information_schema.columns where table_name = 'proc'; select * from t115; table_name column_name column_type proc db char(64) proc name char(64) proc type enum('FUNCTION','PROCEDURE') proc specific_name char(64) proc language enum('SQL') proc sql_data_access enum('CONTAINS_SQL','NO_SQL','READS_SQL_DATA','MODIFIES_SQL_DATA') proc is_deterministic enum('YES','NO') proc security_type enum('INVOKER','DEFINER') proc param_list blob proc returns longblob proc body longblob proc definer char(77) proc created timestamp proc modified timestamp proc sql_mode set('REAL_AS_FLOAT','PIPES_AS_CONCAT','ANSI_QUOTES','IGNORE_SPACE','NOT_USED','ONLY_FULL_GROUP_BY','NO_UNSIGNED_SUBTRACTION','NO_DIR_IN_CREATE','POSTGRESQL','ORACLE','MSSQL','DB2','MAXDB','NO_KEY_OPTIONS','NO_TABLE_OPTIONS','NO_FIELD_OPTIONS','MYSQL323','MYSQL40','ANSI','NO_AUTO_VALUE_ON_ZERO','NO_BACKSLASH_ESCAPES','STRICT_TRANS_TABLES','STRICT_ALL_TABLES','NO_ZERO_IN_DATE','NO_ZERO_DATE','INVALID_DATES','ERROR_FOR_DIVISION_BY_ZERO','TRADITIONAL','NO_AUTO_CREATE_USER','HIGH_NOT_PRECEDENCE','NO_ENGINE_SUBSTITUTION','PAD_CHAR_TO_FULL_LENGTH') proc comment char(64) proc character_set_client char(32) proc collation_connection char(32) proc db_collation char(32) proc body_utf8 longblob drop table t115; create procedure p108 () begin declare c cursor for select data_type from information_schema.columns; open c; open c; end;// call p108()// ERROR 24000: Cursor is already open drop procedure p108; create view v1 as select A1.table_name from information_schema.TABLES A1 where table_name= "user"; select * from v1; table_name user drop view v1; create view vo as select 'a' union select 'a'; show index from vo; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment select * from information_schema.TABLE_CONSTRAINTS where TABLE_NAME= "vo"; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_SCHEMA TABLE_NAME CONSTRAINT_TYPE select * from information_schema.KEY_COLUMN_USAGE where TABLE_NAME= "vo"; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION POSITION_IN_UNIQUE_CONSTRAINT REFERENCED_TABLE_SCHEMA REFERENCED_TABLE_NAME REFERENCED_COLUMN_NAME drop view vo; select TABLE_NAME,TABLE_TYPE,ENGINE from information_schema.tables where table_schema='information_schema' limit 2; TABLE_NAME TABLE_TYPE ENGINE CHARACTER_SETS SYSTEM VIEW MEMORY COLLATIONS SYSTEM VIEW MEMORY show tables from information_schema like "T%"; Tables_in_information_schema (T%) TABLES TABLE_CONSTRAINTS TABLE_PRIVILEGES TRIGGERS create database information_schema; ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema' use information_schema; show full tables like "T%"; Tables_in_information_schema (T%) Table_type TABLES SYSTEM VIEW TABLE_CONSTRAINTS SYSTEM VIEW TABLE_PRIVILEGES SYSTEM VIEW TRIGGERS SYSTEM VIEW create table t1(a int); ERROR 42S02: Unknown table 't1' in information_schema use test; show tables; Tables_in_test use information_schema; show tables like "T%"; Tables_in_information_schema (T%) TABLES TABLE_CONSTRAINTS TABLE_PRIVILEGES TRIGGERS select table_name from tables where table_name='user'; table_name user select column_name, privileges from columns where table_name='user' and column_name like '%o%'; column_name privileges Host select,insert,update,references Password select,insert,update,references Drop_priv select,insert,update,references Reload_priv select,insert,update,references Shutdown_priv select,insert,update,references Process_priv select,insert,update,references Show_db_priv select,insert,update,references Lock_tables_priv select,insert,update,references Show_view_priv select,insert,update,references Create_routine_priv select,insert,update,references Alter_routine_priv select,insert,update,references max_questions select,insert,update,references max_connections select,insert,update,references max_user_connections select,insert,update,references use test; create function sub1(i int) returns int return i+1; create table t1(f1 int); create view v2 (c) as select f1 from t1; create view v3 (c) as select sub1(1); create table t4(f1 int, KEY f1_key (f1)); drop table t1; drop function sub1; select table_name from information_schema.views where table_schema='test'; table_name v2 v3 select table_name from information_schema.views where table_schema='test'; table_name v2 v3 select column_name from information_schema.columns where table_schema='test'; column_name f1 Warnings: Warning 1356 View 'test.v2' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them Warning 1356 View 'test.v3' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them select index_name from information_schema.statistics where table_schema='test'; index_name f1_key select constraint_name from information_schema.table_constraints where table_schema='test'; constraint_name show create view v2; View Create View character_set_client collation_connection v2 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v2` AS select `test`.`t1`.`f1` AS `c` from `t1` latin1 latin1_swedish_ci Warnings: Warning 1356 View 'test.v2' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them show create table v3; View Create View character_set_client collation_connection v3 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v3` AS select `sub1`(1) AS `c` latin1 latin1_swedish_ci Warnings: Warning 1356 View 'test.v3' references invalid table(s) or column(s) or function(s) or definer/invoker of view lack rights to use them drop view v2; drop view v3; drop table t4; select * from information_schema.table_names; ERROR 42S02: Unknown table 'table_names' in information_schema select column_type from information_schema.columns where table_schema="information_schema" and table_name="COLUMNS" and (column_name="character_set_name" or column_name="collation_name"); column_type varchar(32) varchar(32) select TABLE_ROWS from information_schema.tables where table_schema="information_schema" and table_name="COLUMNS"; TABLE_ROWS NULL select table_type from information_schema.tables where table_schema="mysql" and table_name="user"; table_type BASE TABLE show open tables where `table` like "user"; Database Table In_use Name_locked mysql user 0 0 show status where variable_name like "%database%"; Variable_name Value Com_show_databases 3 show variables where variable_name like "skip_show_databas"; Variable_name Value show global status like "Threads_running"; Variable_name Value Threads_running # create table t1(f1 int); create table t2(f2 int); create view v1 as select * from t1, t2; set @got_val= (select count(*) from information_schema.columns); drop view v1; drop table t1, t2; use test; CREATE TABLE t_crashme ( f1 BIGINT); CREATE VIEW a1 (t_CRASHME) AS SELECT f1 FROM t_crashme GROUP BY f1; CREATE VIEW a2 AS SELECT t_CRASHME FROM a1; count(*) 68 drop view a2, a1; drop table t_crashme; select table_schema,table_name, column_name from information_schema.columns where data_type = 'longtext'; table_schema table_name column_name information_schema COLUMNS COLUMN_DEFAULT information_schema COLUMNS COLUMN_TYPE information_schema EVENTS EVENT_DEFINITION information_schema PARTITIONS PARTITION_EXPRESSION information_schema PARTITIONS SUBPARTITION_EXPRESSION information_schema PARTITIONS PARTITION_DESCRIPTION information_schema PLUGINS PLUGIN_DESCRIPTION information_schema PROCESSLIST INFO information_schema ROUTINES ROUTINE_DEFINITION information_schema TRIGGERS ACTION_CONDITION information_schema TRIGGERS ACTION_STATEMENT information_schema VIEWS VIEW_DEFINITION select table_name, column_name, data_type from information_schema.columns where data_type = 'datetime'; table_name column_name data_type EVENTS EXECUTE_AT datetime EVENTS STARTS datetime EVENTS ENDS datetime EVENTS CREATED datetime EVENTS LAST_ALTERED datetime EVENTS LAST_EXECUTED datetime FILES CREATION_TIME datetime FILES LAST_UPDATE_TIME datetime FILES LAST_ACCESS_TIME datetime FILES CREATE_TIME datetime FILES UPDATE_TIME datetime FILES CHECK_TIME datetime PARTITIONS CREATE_TIME datetime PARTITIONS UPDATE_TIME datetime PARTITIONS CHECK_TIME datetime ROUTINES CREATED datetime ROUTINES LAST_ALTERED datetime TABLES CREATE_TIME datetime TABLES UPDATE_TIME datetime TABLES CHECK_TIME datetime TRIGGERS CREATED datetime event execute_at datetime event last_executed datetime event starts datetime event ends datetime SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES A WHERE NOT EXISTS (SELECT * FROM INFORMATION_SCHEMA.COLUMNS B WHERE A.TABLE_SCHEMA = B.TABLE_SCHEMA AND A.TABLE_NAME = B.TABLE_NAME); COUNT(*) 0 create table t1 ( x_bigint BIGINT, x_integer INTEGER, x_smallint SMALLINT, x_decimal DECIMAL(5,3), x_numeric NUMERIC(5,3), x_real REAL, x_float FLOAT, x_double_precision DOUBLE PRECISION ); SELECT COLUMN_NAME, CHARACTER_MAXIMUM_LENGTH, CHARACTER_OCTET_LENGTH FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME= 't1'; COLUMN_NAME CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH x_bigint NULL NULL x_integer NULL NULL x_smallint NULL NULL x_decimal NULL NULL x_numeric NULL NULL x_real NULL NULL x_float NULL NULL x_double_precision NULL NULL drop table t1; grant select on test.* to mysqltest_4@localhost; SELECT TABLE_NAME, COLUMN_NAME, PRIVILEGES FROM INFORMATION_SCHEMA.COLUMNS where COLUMN_NAME='TABLE_NAME'; TABLE_NAME COLUMN_NAME PRIVILEGES COLUMNS TABLE_NAME select COLUMN_PRIVILEGES TABLE_NAME select FILES TABLE_NAME select KEY_COLUMN_USAGE TABLE_NAME select PARTITIONS TABLE_NAME select REFERENTIAL_CONSTRAINTS TABLE_NAME select STATISTICS TABLE_NAME select TABLES TABLE_NAME select TABLE_CONSTRAINTS TABLE_NAME select TABLE_PRIVILEGES TABLE_NAME select VIEWS TABLE_NAME select delete from mysql.user where user='mysqltest_4'; delete from mysql.db where user='mysqltest_4'; flush privileges; SELECT table_schema, count(*) FROM information_schema.TABLES WHERE table_schema IN ('mysql', 'INFORMATION_SCHEMA', 'test', 'mysqltest') AND table_name<>'ndb_binlog_index' AND table_name<>'ndb_apply_status' GROUP BY TABLE_SCHEMA; table_schema count(*) information_schema 28 mysql 22 create table t1 (i int, j int); create trigger trg1 before insert on t1 for each row begin if new.j > 10 then set new.j := 10; end if; end| create trigger trg2 before update on t1 for each row begin if old.i % 2 = 0 then set new.j := -1; end if; end| create trigger trg3 after update on t1 for each row begin if new.j = -1 then set @fired:= "Yes"; end if; end| show triggers; Trigger Event Table Statement Timing Created sql_mode Definer character_set_client collation_connection Database Collation trg1 INSERT t1 begin if new.j > 10 then set new.j := 10; end if; end BEFORE NULL root@localhost latin1 latin1_swedish_ci latin1_swedish_ci trg2 UPDATE t1 begin if old.i % 2 = 0 then set new.j := -1; end if; end BEFORE NULL root@localhost latin1 latin1_swedish_ci latin1_swedish_ci trg3 UPDATE t1 begin if new.j = -1 then set @fired:= "Yes"; end if; end AFTER NULL root@localhost latin1 latin1_swedish_ci latin1_swedish_ci select * from information_schema.triggers where trigger_schema in ('mysql', 'information_schema', 'test', 'mysqltest'); TRIGGER_CATALOG TRIGGER_SCHEMA TRIGGER_NAME EVENT_MANIPULATION EVENT_OBJECT_CATALOG EVENT_OBJECT_SCHEMA EVENT_OBJECT_TABLE ACTION_ORDER ACTION_CONDITION ACTION_STATEMENT ACTION_ORIENTATION ACTION_TIMING ACTION_REFERENCE_OLD_TABLE ACTION_REFERENCE_NEW_TABLE ACTION_REFERENCE_OLD_ROW ACTION_REFERENCE_NEW_ROW CREATED SQL_MODE DEFINER CHARACTER_SET_CLIENT COLLATION_CONNECTION DATABASE_COLLATION NULL test trg1 INSERT NULL test t1 0 NULL begin if new.j > 10 then set new.j := 10; end if; end ROW BEFORE NULL NULL OLD NEW NULL root@localhost latin1 latin1_swedish_ci latin1_swedish_ci NULL test trg2 UPDATE NULL test t1 0 NULL begin if old.i % 2 = 0 then set new.j := -1; end if; end ROW BEFORE NULL NULL OLD NEW NULL root@localhost latin1 latin1_swedish_ci latin1_swedish_ci NULL test trg3 UPDATE NULL test t1 0 NULL begin if new.j = -1 then set @fired:= "Yes"; end if; end ROW AFTER NULL NULL OLD NEW NULL root@localhost latin1 latin1_swedish_ci latin1_swedish_ci drop trigger trg1; drop trigger trg2; drop trigger trg3; drop table t1; create database mysqltest; create table mysqltest.t1 (f1 int, f2 int); create table mysqltest.t2 (f1 int); grant select (f1) on mysqltest.t1 to user1@localhost; grant select on mysqltest.t2 to user2@localhost; grant select on mysqltest.* to user3@localhost; grant select on *.* to user4@localhost; select * from information_schema.column_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME PRIVILEGE_TYPE IS_GRANTABLE 'user1'@'localhost' NULL mysqltest t1 f1 SELECT NO select * from information_schema.table_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PRIVILEGE_TYPE IS_GRANTABLE select * from information_schema.schema_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA PRIVILEGE_TYPE IS_GRANTABLE select * from information_schema.user_privileges order by grantee; GRANTEE TABLE_CATALOG PRIVILEGE_TYPE IS_GRANTABLE 'user1'@'localhost' NULL USAGE NO show grants; Grants for user1@localhost GRANT USAGE ON *.* TO 'user1'@'localhost' GRANT SELECT (f1) ON `mysqltest`.`t1` TO 'user1'@'localhost' select * from information_schema.column_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME PRIVILEGE_TYPE IS_GRANTABLE select * from information_schema.table_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PRIVILEGE_TYPE IS_GRANTABLE 'user2'@'localhost' NULL mysqltest t2 SELECT NO select * from information_schema.schema_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA PRIVILEGE_TYPE IS_GRANTABLE select * from information_schema.user_privileges order by grantee; GRANTEE TABLE_CATALOG PRIVILEGE_TYPE IS_GRANTABLE 'user2'@'localhost' NULL USAGE NO show grants; Grants for user2@localhost GRANT USAGE ON *.* TO 'user2'@'localhost' GRANT SELECT ON `mysqltest`.`t2` TO 'user2'@'localhost' select * from information_schema.column_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME PRIVILEGE_TYPE IS_GRANTABLE select * from information_schema.table_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PRIVILEGE_TYPE IS_GRANTABLE select * from information_schema.schema_privileges order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA PRIVILEGE_TYPE IS_GRANTABLE 'user3'@'localhost' NULL mysqltest SELECT NO select * from information_schema.user_privileges order by grantee; GRANTEE TABLE_CATALOG PRIVILEGE_TYPE IS_GRANTABLE 'user3'@'localhost' NULL USAGE NO show grants; Grants for user3@localhost GRANT USAGE ON *.* TO 'user3'@'localhost' GRANT SELECT ON `mysqltest`.* TO 'user3'@'localhost' select * from information_schema.column_privileges where grantee like '%user%' order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME PRIVILEGE_TYPE IS_GRANTABLE 'user1'@'localhost' NULL mysqltest t1 f1 SELECT NO select * from information_schema.table_privileges where grantee like '%user%' order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PRIVILEGE_TYPE IS_GRANTABLE 'user2'@'localhost' NULL mysqltest t2 SELECT NO select * from information_schema.schema_privileges where grantee like '%user%' order by grantee; GRANTEE TABLE_CATALOG TABLE_SCHEMA PRIVILEGE_TYPE IS_GRANTABLE 'user3'@'localhost' NULL mysqltest SELECT NO select * from information_schema.user_privileges where grantee like '%user%' order by grantee; GRANTEE TABLE_CATALOG PRIVILEGE_TYPE IS_GRANTABLE 'user1'@'localhost' NULL USAGE NO 'user2'@'localhost' NULL USAGE NO 'user3'@'localhost' NULL USAGE NO 'user4'@'localhost' NULL SELECT NO show grants; Grants for user4@localhost GRANT SELECT ON *.* TO 'user4'@'localhost' drop user user1@localhost, user2@localhost, user3@localhost, user4@localhost; use test; drop database mysqltest; drop procedure if exists p1; drop procedure if exists p2; create procedure p1 () modifies sql data set @a = 5; create procedure p2 () set @a = 5; select sql_data_access from information_schema.routines where specific_name like 'p%'; sql_data_access MODIFIES SQL DATA CONTAINS SQL drop procedure p1; drop procedure p2; show create database information_schema; Database Create Database information_schema CREATE DATABASE `information_schema` /*!40100 DEFAULT CHARACTER SET utf8 */ create table t1(f1 LONGBLOB, f2 LONGTEXT); select column_name,data_type,CHARACTER_OCTET_LENGTH, CHARACTER_MAXIMUM_LENGTH from information_schema.columns where table_name='t1'; column_name data_type CHARACTER_OCTET_LENGTH CHARACTER_MAXIMUM_LENGTH f1 longblob 4294967295 4294967295 f2 longtext 4294967295 4294967295 drop table t1; create table t1(f1 tinyint, f2 SMALLINT, f3 mediumint, f4 int, f5 BIGINT, f6 BIT, f7 bit(64)); select column_name, NUMERIC_PRECISION, NUMERIC_SCALE from information_schema.columns where table_name='t1'; column_name NUMERIC_PRECISION NUMERIC_SCALE f1 3 0 f2 5 0 f3 7 0 f4 10 0 f5 19 0 f6 1 NULL f7 64 NULL drop table t1; create table t1 (f1 integer); create trigger tr1 after insert on t1 for each row set @test_var=42; use information_schema; select trigger_schema, trigger_name from triggers where trigger_name='tr1'; trigger_schema trigger_name test tr1 use test; drop table t1; create table t1 (a int not null, b int); use information_schema; select column_name, column_default from columns where table_schema='test' and table_name='t1'; column_name column_default a NULL b NULL use test; show columns from t1; Field Type Null Key Default Extra a int(11) NO NULL b int(11) YES NULL drop table t1; CREATE TABLE t1 (a int); CREATE TABLE t2 (b int); SHOW TABLE STATUS FROM test WHERE name IN ( SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA='test' AND TABLE_TYPE='BASE TABLE'); Name Engine Version Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Collation Checksum Create_options Comment t1 MyISAM 10 Fixed 0 0 0 # 1024 0 NULL # # NULL latin1_swedish_ci NULL t2 MyISAM 10 Fixed 0 0 0 # 1024 0 NULL # # NULL latin1_swedish_ci NULL DROP TABLE t1,t2; create table t1(f1 int); create view v1 (c) as select f1 from t1; select database(); database() NULL show fields from test.v1; Field Type Null Key Default Extra c int(11) YES NULL drop view v1; drop table t1; alter database information_schema; ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 drop database information_schema; ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema' drop table information_schema.tables; ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema' alter table information_schema.tables; ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema' use information_schema; create temporary table schemata(f1 char(10)); ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema' CREATE PROCEDURE p1 () BEGIN SELECT 'foo' FROM DUAL; END | ERROR 42000: Unknown database 'information_schema' select ROUTINE_NAME from routines where ROUTINE_SCHEMA='information_schema'; ROUTINE_NAME grant all on information_schema.* to 'user1'@'localhost'; ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema' grant select on information_schema.* to 'user1'@'localhost'; ERROR 42000: Access denied for user 'root'@'localhost' to database 'information_schema' use test; create table t1(id int); insert into t1(id) values (1); select 1 from (select 1 from test.t1) a; 1 1 use information_schema; select 1 from (select 1 from test.t1) a; 1 1 use test; drop table t1; create table t1 (f1 int(11)); create view v1 as select * from t1; drop table t1; select table_type from information_schema.tables where table_name="v1"; table_type VIEW drop view v1; create temporary table t1(f1 int, index(f1)); show columns from t1; Field Type Null Key Default Extra f1 int(11) YES MUL NULL describe t1; Field Type Null Key Default Extra f1 int(11) YES MUL NULL show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment t1 1 f1 1 f1 A NULL NULL NULL YES BTREE drop table t1; create table t1(f1 binary(32), f2 varbinary(64)); select character_maximum_length, character_octet_length from information_schema.columns where table_name='t1'; character_maximum_length character_octet_length 32 32 64 64 drop table t1; CREATE TABLE t1 (f1 BIGINT, f2 VARCHAR(20), f3 BIGINT); INSERT INTO t1 SET f1 = 1, f2 = 'Schoenenbourg', f3 = 1; CREATE FUNCTION func2() RETURNS BIGINT RETURN 1; CREATE FUNCTION func1() RETURNS BIGINT BEGIN RETURN ( SELECT COUNT(*) FROM INFORMATION_SCHEMA.VIEWS); END// CREATE VIEW v1 AS SELECT 1 FROM t1 WHERE f3 = (SELECT func2 ()); SELECT func1(); func1() 1 DROP TABLE t1; DROP VIEW v1; DROP FUNCTION func1; DROP FUNCTION func2; select column_type, group_concat(table_schema, '.', table_name), count(*) as num from information_schema.columns where table_schema='information_schema' and (column_type = 'varchar(7)' or column_type = 'varchar(20)' or column_type = 'varchar(27)') group by column_type order by num; column_type group_concat(table_schema, '.', table_name) num varchar(27) information_schema.COLUMNS 1 varchar(7) information_schema.ROUTINES,information_schema.VIEWS 2 varchar(20) information_schema.FILES,information_schema.FILES,information_schema.PLUGINS,information_schema.PLUGINS,information_schema.PLUGINS,information_schema.PROFILING 6 create table t1(f1 char(1) not null, f2 char(9) not null) default character set utf8; select CHARACTER_MAXIMUM_LENGTH, CHARACTER_OCTET_LENGTH from information_schema.columns where table_schema='test' and table_name = 't1'; CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH 1 3 9 27 drop table t1; use mysql; INSERT INTO `proc` VALUES ('test','','PROCEDURE','','SQL','CONTAINS_SQL', 'NO','DEFINER','','','BEGIN\r\n \r\nEND','root@%','2006-03-02 18:40:03', '2006-03-02 18:40:03','','','utf8','utf8_general_ci','utf8_general_ci','n/a'); select routine_name from information_schema.routines where ROUTINE_SCHEMA='test'; routine_name delete from proc where name=''; use test; grant select on test.* to mysqltest_1@localhost; create table t1 (id int); create view v1 as select * from t1; create definer = mysqltest_1@localhost sql security definer view v2 as select 1; select * from information_schema.views where table_name='v1' or table_name='v2'; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME VIEW_DEFINITION CHECK_OPTION IS_UPDATABLE DEFINER SECURITY_TYPE CHARACTER_SET_CLIENT COLLATION_CONNECTION NULL test v1 NONE YES root@localhost DEFINER latin1 latin1_swedish_ci NULL test v2 select 1 AS `1` NONE NO mysqltest_1@localhost DEFINER latin1 latin1_swedish_ci drop view v1, v2; drop table t1; drop user mysqltest_1@localhost; set @a:= '.'; create table t1(f1 char(5)); create table t2(f1 char(5)); select concat(@a, table_name), @a, table_name from information_schema.tables where table_schema = 'test'; concat(@a, table_name) @a table_name .t1 . t1 .t2 . t2 drop table t1,t2; DROP PROCEDURE IF EXISTS p1; DROP FUNCTION IF EXISTS f1; CREATE PROCEDURE p1() SET @a= 1; CREATE FUNCTION f1() RETURNS INT RETURN @a + 1; CREATE USER mysql_bug20230@localhost; GRANT EXECUTE ON PROCEDURE p1 TO mysql_bug20230@localhost; GRANT EXECUTE ON FUNCTION f1 TO mysql_bug20230@localhost; SELECT ROUTINE_NAME, ROUTINE_DEFINITION FROM INFORMATION_SCHEMA.ROUTINES WHERE ROUTINE_SCHEMA='test'; ROUTINE_NAME ROUTINE_DEFINITION f1 RETURN @a + 1 p1 SET @a= 1 SHOW CREATE PROCEDURE p1; Procedure sql_mode Create Procedure character_set_client collation_connection Database Collation p1 CREATE DEFINER=`root`@`localhost` PROCEDURE `p1`() SET @a= 1 latin1 latin1_swedish_ci latin1_swedish_ci SHOW CREATE FUNCTION f1; Function sql_mode Create Function character_set_client collation_connection Database Collation f1 CREATE DEFINER=`root`@`localhost` FUNCTION `f1`() RETURNS int(11) RETURN @a + 1 latin1 latin1_swedish_ci latin1_swedish_ci SELECT ROUTINE_NAME, ROUTINE_DEFINITION FROM INFORMATION_SCHEMA.ROUTINES WHERE ROUTINE_SCHEMA='test'; ROUTINE_NAME ROUTINE_DEFINITION f1 NULL p1 NULL SHOW CREATE PROCEDURE p1; Procedure sql_mode Create Procedure character_set_client collation_connection Database Collation p1 NULL latin1 latin1_swedish_ci latin1_swedish_ci SHOW CREATE FUNCTION f1; Function sql_mode Create Function character_set_client collation_connection Database Collation f1 NULL latin1 latin1_swedish_ci latin1_swedish_ci CALL p1(); SELECT f1(); f1() 2 DROP FUNCTION f1; DROP PROCEDURE p1; DROP USER mysql_bug20230@localhost; SELECT t.table_name, c1.column_name FROM information_schema.tables t INNER JOIN information_schema.columns c1 ON t.table_schema = c1.table_schema AND t.table_name = c1.table_name WHERE t.table_schema = 'information_schema' AND c1.ordinal_position = ( SELECT COALESCE(MIN(c2.ordinal_position),1) FROM information_schema.columns c2 WHERE c2.table_schema = t.table_schema AND c2.table_name = t.table_name AND c2.column_name LIKE '%SCHEMA%' ); table_name column_name CHARACTER_SETS CHARACTER_SET_NAME COLLATIONS COLLATION_NAME COLLATION_CHARACTER_SET_APPLICABILITY COLLATION_NAME COLUMNS TABLE_SCHEMA COLUMN_PRIVILEGES TABLE_SCHEMA ENGINES ENGINE EVENTS EVENT_SCHEMA FILES TABLE_SCHEMA GLOBAL_STATUS VARIABLE_NAME GLOBAL_VARIABLES VARIABLE_NAME KEY_COLUMN_USAGE CONSTRAINT_SCHEMA PARTITIONS TABLE_SCHEMA PLUGINS PLUGIN_NAME PROCESSLIST ID PROFILING QUERY_ID REFERENTIAL_CONSTRAINTS CONSTRAINT_SCHEMA ROUTINES ROUTINE_SCHEMA SCHEMATA SCHEMA_NAME SCHEMA_PRIVILEGES TABLE_SCHEMA SESSION_STATUS VARIABLE_NAME SESSION_VARIABLES VARIABLE_NAME STATISTICS TABLE_SCHEMA TABLES TABLE_SCHEMA TABLE_CONSTRAINTS CONSTRAINT_SCHEMA TABLE_PRIVILEGES TABLE_SCHEMA TRIGGERS TRIGGER_SCHEMA USER_PRIVILEGES GRANTEE VIEWS TABLE_SCHEMA SELECT t.table_name, c1.column_name FROM information_schema.tables t INNER JOIN information_schema.columns c1 ON t.table_schema = c1.table_schema AND t.table_name = c1.table_name WHERE t.table_schema = 'information_schema' AND c1.ordinal_position = ( SELECT COALESCE(MIN(c2.ordinal_position),1) FROM information_schema.columns c2 WHERE c2.table_schema = 'information_schema' AND c2.table_name = t.table_name AND c2.column_name LIKE '%SCHEMA%' ); table_name column_name CHARACTER_SETS CHARACTER_SET_NAME COLLATIONS COLLATION_NAME COLLATION_CHARACTER_SET_APPLICABILITY COLLATION_NAME COLUMNS TABLE_SCHEMA COLUMN_PRIVILEGES TABLE_SCHEMA ENGINES ENGINE EVENTS EVENT_SCHEMA FILES TABLE_SCHEMA GLOBAL_STATUS VARIABLE_NAME GLOBAL_VARIABLES VARIABLE_NAME KEY_COLUMN_USAGE CONSTRAINT_SCHEMA PARTITIONS TABLE_SCHEMA PLUGINS PLUGIN_NAME PROCESSLIST ID PROFILING QUERY_ID REFERENTIAL_CONSTRAINTS CONSTRAINT_SCHEMA ROUTINES ROUTINE_SCHEMA SCHEMATA SCHEMA_NAME SCHEMA_PRIVILEGES TABLE_SCHEMA SESSION_STATUS VARIABLE_NAME SESSION_VARIABLES VARIABLE_NAME STATISTICS TABLE_SCHEMA TABLES TABLE_SCHEMA TABLE_CONSTRAINTS CONSTRAINT_SCHEMA TABLE_PRIVILEGES TABLE_SCHEMA TRIGGERS TRIGGER_SCHEMA USER_PRIVILEGES GRANTEE VIEWS TABLE_SCHEMA SELECT MAX(table_name) FROM information_schema.tables WHERE table_schema IN ('mysql', 'INFORMATION_SCHEMA', 'test'); MAX(table_name) VIEWS SELECT table_name from information_schema.tables WHERE table_name=(SELECT MAX(table_name) FROM information_schema.tables WHERE table_schema IN ('mysql', 'INFORMATION_SCHEMA', 'test')); table_name VIEWS DROP TABLE IF EXISTS bug23037; DROP FUNCTION IF EXISTS get_value; SELECT COLUMN_NAME, MD5(COLUMN_DEFAULT), LENGTH(COLUMN_DEFAULT) FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='bug23037'; COLUMN_NAME MD5(COLUMN_DEFAULT) LENGTH(COLUMN_DEFAULT) fld1 7cf7a6782be951a1f2464a350da926a5 65532 SELECT MD5(get_value()); MD5(get_value()) 7cf7a6782be951a1f2464a350da926a5 SELECT COLUMN_NAME, MD5(COLUMN_DEFAULT), LENGTH(COLUMN_DEFAULT), COLUMN_DEFAULT=get_value() FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='bug23037'; COLUMN_NAME MD5(COLUMN_DEFAULT) LENGTH(COLUMN_DEFAULT) COLUMN_DEFAULT=get_value() fld1 7cf7a6782be951a1f2464a350da926a5 65532 1 DROP TABLE bug23037; DROP FUNCTION get_value; create view v1 as select table_schema as object_schema, table_name as object_name, table_type as object_type from information_schema.tables order by object_schema; explain select * from v1; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE tables ALL NULL NULL NULL NULL NULL Open_frm_only; Scanned all databases; Using filesort explain select * from (select table_name from information_schema.tables) as a; id select_type table type possible_keys key key_len ref rows Extra 1 PRIMARY system NULL NULL NULL NULL 0 const row not found 2 DERIVED tables ALL NULL NULL NULL NULL NULL Skip_open_table; Scanned all databases drop view v1; create table t1 (f1 int(11)); create table t2 (f1 int(11), f2 int(11)); select table_name from information_schema.tables where table_schema = 'test' and table_name not in (select table_name from information_schema.columns where table_schema = 'test' and column_name = 'f3'); table_name t1 t2 drop table t1,t2; select 1 as f1 from information_schema.tables where "CHARACTER_SETS"= (select cast(table_name as char) from information_schema.tables order by table_name limit 1) limit 1; f1 1 select t.table_name, group_concat(t.table_schema, '.', t.table_name), count(*) as num1 from information_schema.tables t inner join information_schema.columns c1 on t.table_schema = c1.table_schema AND t.table_name = c1.table_name where t.table_schema = 'information_schema' and c1.ordinal_position = (select isnull(c2.column_type) - isnull(group_concat(c2.table_schema, '.', c2.table_name)) + count(*) as num from information_schema.columns c2 where c2.table_schema='information_schema' and (c2.column_type = 'varchar(7)' or c2.column_type = 'varchar(20)') group by c2.column_type order by num limit 1) group by t.table_name order by num1, t.table_name; table_name group_concat(t.table_schema, '.', t.table_name) num1 CHARACTER_SETS information_schema.CHARACTER_SETS 1 COLLATIONS information_schema.COLLATIONS 1 COLLATION_CHARACTER_SET_APPLICABILITY information_schema.COLLATION_CHARACTER_SET_APPLICABILITY 1 COLUMNS information_schema.COLUMNS 1 COLUMN_PRIVILEGES information_schema.COLUMN_PRIVILEGES 1 ENGINES information_schema.ENGINES 1 EVENTS information_schema.EVENTS 1 FILES information_schema.FILES 1 GLOBAL_STATUS information_schema.GLOBAL_STATUS 1 GLOBAL_VARIABLES information_schema.GLOBAL_VARIABLES 1 KEY_COLUMN_USAGE information_schema.KEY_COLUMN_USAGE 1 PARTITIONS information_schema.PARTITIONS 1 PLUGINS information_schema.PLUGINS 1 PROCESSLIST information_schema.PROCESSLIST 1 PROFILING information_schema.PROFILING 1 REFERENTIAL_CONSTRAINTS information_schema.REFERENTIAL_CONSTRAINTS 1 ROUTINES information_schema.ROUTINES 1 SCHEMATA information_schema.SCHEMATA 1 SCHEMA_PRIVILEGES information_schema.SCHEMA_PRIVILEGES 1 SESSION_STATUS information_schema.SESSION_STATUS 1 SESSION_VARIABLES information_schema.SESSION_VARIABLES 1 STATISTICS information_schema.STATISTICS 1 TABLES information_schema.TABLES 1 TABLE_CONSTRAINTS information_schema.TABLE_CONSTRAINTS 1 TABLE_PRIVILEGES information_schema.TABLE_PRIVILEGES 1 TRIGGERS information_schema.TRIGGERS 1 USER_PRIVILEGES information_schema.USER_PRIVILEGES 1 VIEWS information_schema.VIEWS 1 create table t1(f1 int); create view v1 as select f1+1 as a from t1; create table t2 (f1 int, f2 int); create view v2 as select f1+1 as a, f2 as b from t2; select table_name, is_updatable from information_schema.views; table_name is_updatable v1 NO v2 YES delete from v1; drop view v1,v2; drop table t1,t2; alter database; ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 alter database test; ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 create database mysqltest; create table mysqltest.t1(a int, b int, c int); create trigger mysqltest.t1_ai after insert on mysqltest.t1 for each row set @a = new.a + new.b + new.c; grant select(b) on mysqltest.t1 to mysqltest_1@localhost; select trigger_name from information_schema.triggers where event_object_table='t1'; trigger_name t1_ai show triggers from mysqltest; Trigger Event Table Statement Timing Created sql_mode Definer character_set_client collation_connection Database Collation t1_ai INSERT t1 set @a = new.a + new.b + new.c AFTER NULL root@localhost latin1 latin1_swedish_ci latin1_swedish_ci show columns from t1; Field Type Null Key Default Extra b int(11) YES NULL select column_name from information_schema.columns where table_name='t1'; column_name b show triggers; Trigger Event Table Statement Timing Created sql_mode Definer character_set_client collation_connection Database Collation select trigger_name from information_schema.triggers where event_object_table='t1'; trigger_name drop user mysqltest_1@localhost; drop database mysqltest; create table t1 ( f1 varchar(50), f2 varchar(50) not null, f3 varchar(50) default '', f4 varchar(50) default NULL, f5 bigint not null, f6 bigint not null default 10, f7 datetime not null, f8 datetime default '2006-01-01' ); select column_default from information_schema.columns where table_name= 't1'; column_default NULL NULL NULL NULL 10 NULL 2006-01-01 00:00:00 show columns from t1; Field Type Null Key Default Extra f1 varchar(50) YES NULL f2 varchar(50) NO NULL f3 varchar(50) YES f4 varchar(50) YES NULL f5 bigint(20) NO NULL f6 bigint(20) NO 10 f7 datetime NO NULL f8 datetime YES 2006-01-01 00:00:00 drop table t1; show fields from information_schema.table_names; ERROR 42S02: Unknown table 'table_names' in information_schema show keys from information_schema.table_names; ERROR 42S02: Unknown table 'table_names' in information_schema USE information_schema; SET max_heap_table_size = 16384; CREATE TABLE test.t1( a INT ); SELECT * FROM tables ta JOIN collations co ON ( co.collation_name = ta.table_catalog ) JOIN character_sets cs ON ( cs.character_set_name = ta.table_catalog ); TABLE_CATALOG TABLE_SCHEMA TABLE_NAME TABLE_TYPE ENGINE VERSION ROW_FORMAT TABLE_ROWS AVG_ROW_LENGTH DATA_LENGTH MAX_DATA_LENGTH INDEX_LENGTH DATA_FREE AUTO_INCREMENT CREATE_TIME UPDATE_TIME CHECK_TIME TABLE_COLLATION CHECKSUM CREATE_OPTIONS TABLE_COMMENT COLLATION_NAME CHARACTER_SET_NAME ID IS_DEFAULT IS_COMPILED SORTLEN CHARACTER_SET_NAME DEFAULT_COLLATE_NAME DESCRIPTION MAXLEN DROP TABLE test.t1; SET max_heap_table_size = DEFAULT; USE test; End of 5.0 tests. select * from information_schema.engines WHERE ENGINE="MyISAM"; ENGINE SUPPORT COMMENT TRANSACTIONS XA SAVEPOINTS MyISAM DEFAULT Default engine as of MySQL 3.23 with great performance NO NO NO grant select on *.* to user3148@localhost; select user,db from information_schema.processlist; user db user3148 test drop user user3148@localhost; DROP TABLE IF EXISTS server_status; DROP EVENT IF EXISTS event_status; SET GLOBAL event_scheduler=1; CREATE EVENT event_status ON SCHEDULE AT NOW() ON COMPLETION NOT PRESERVE DO BEGIN CREATE TABLE server_status SELECT variable_name FROM information_schema.global_status WHERE variable_name LIKE 'ABORTED_CONNECTS' OR variable_name LIKE 'BINLOG_CACHE_DISK_USE'; END$$ SELECT variable_name FROM server_status; variable_name ABORTED_CONNECTS BINLOG_CACHE_DISK_USE DROP TABLE server_status; SET GLOBAL event_scheduler=0; explain select table_name from information_schema.views where table_schema='test' and table_name='v1'; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE views ALL NULL TABLE_SCHEMA,TABLE_NAME NULL NULL NULL Using where; Open_frm_only; Scanned 0 databases explain select * from information_schema.tables; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE tables ALL NULL NULL NULL NULL NULL Open_full_table; Scanned all databases explain select * from information_schema.collations; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE collations ALL NULL NULL NULL NULL NULL explain select * from information_schema.tables where table_schema='test' and table_name= 't1'; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE tables ALL NULL TABLE_SCHEMA,TABLE_NAME NULL NULL NULL Using where; Open_full_table; Scanned 0 databases explain select table_name, table_type from information_schema.tables where table_schema='test'; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE tables ALL NULL TABLE_SCHEMA NULL NULL NULL Using where; Open_frm_only; Scanned 1 database explain select b.table_name from information_schema.tables a, information_schema.columns b where a.table_name='t1' and a.table_schema='test' and b.table_name=a.table_name; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE a ALL NULL TABLE_SCHEMA,TABLE_NAME NULL NULL NULL Using where; Skip_open_table; Scanned 0 databases 1 SIMPLE b ALL NULL NULL NULL NULL NULL Using where; Open_frm_only; Scanned all databases; Using join buffer SELECT * FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = 'mysqltest'; CATALOG_NAME SCHEMA_NAME DEFAULT_CHARACTER_SET_NAME DEFAULT_COLLATION_NAME SQL_PATH SELECT * FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = ''; CATALOG_NAME SCHEMA_NAME DEFAULT_CHARACTER_SET_NAME DEFAULT_COLLATION_NAME SQL_PATH SELECT * FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = 'test'; CATALOG_NAME SCHEMA_NAME DEFAULT_CHARACTER_SET_NAME DEFAULT_COLLATION_NAME SQL_PATH NULL test latin1 latin1_swedish_ci NULL select count(*) from INFORMATION_SCHEMA.TABLES where TABLE_SCHEMA='mysql' AND TABLE_NAME='nonexisting'; count(*) 0 select count(*) from INFORMATION_SCHEMA.TABLES where TABLE_SCHEMA='mysql' AND TABLE_NAME=''; count(*) 0 select count(*) from INFORMATION_SCHEMA.TABLES where TABLE_SCHEMA='' AND TABLE_NAME=''; count(*) 0 select count(*) from INFORMATION_SCHEMA.TABLES where TABLE_SCHEMA='' AND TABLE_NAME='nonexisting'; count(*) 0 CREATE VIEW v1 AS SELECT * FROM information_schema.tables; SELECT VIEW_DEFINITION FROM INFORMATION_SCHEMA.VIEWS where TABLE_NAME = 'v1'; VIEW_DEFINITION select `tables`.`TABLE_CATALOG` AS `TABLE_CATALOG`,`tables`.`TABLE_SCHEMA` AS `TABLE_SCHEMA`,`tables`.`TABLE_NAME` AS `TABLE_NAME`,`tables`.`TABLE_TYPE` AS `TABLE_TYPE`,`tables`.`ENGINE` AS `ENGINE`,`tables`.`VERSION` AS `VERSION`,`tables`.`ROW_FORMAT` AS `ROW_FORMAT`,`tables`.`TABLE_ROWS` AS `TABLE_ROWS`,`tables`.`AVG_ROW_LENGTH` AS `AVG_ROW_LENGTH`,`tables`.`DATA_LENGTH` AS `DATA_LENGTH`,`tables`.`MAX_DATA_LENGTH` AS `MAX_DATA_LENGTH`,`tables`.`INDEX_LENGTH` AS `INDEX_LENGTH`,`tables`.`DATA_FREE` AS `DATA_FREE`,`tables`.`AUTO_INCREMENT` AS `AUTO_INCREMENT`,`tables`.`CREATE_TIME` AS `CREATE_TIME`,`tables`.`UPDATE_TIME` AS `UPDATE_TIME`,`tables`.`CHECK_TIME` AS `CHECK_TIME`,`tables`.`TABLE_COLLATION` AS `TABLE_COLLATION`,`tables`.`CHECKSUM` AS `CHECKSUM`,`tables`.`CREATE_OPTIONS` AS `CREATE_OPTIONS`,`tables`.`TABLE_COMMENT` AS `TABLE_COMMENT` from `information_schema`.`tables` DROP VIEW v1; SELECT SCHEMA_NAME FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME ='information_schema'; SCHEMA_NAME information_schema SELECT TABLE_COLLATION FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA='mysql' and TABLE_NAME= 'db'; TABLE_COLLATION utf8_bin select * from information_schema.columns where table_schema = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE COLUMN_KEY EXTRA PRIVILEGES COLUMN_COMMENT STORAGE FORMAT select * from `information_schema`.`COLUMNS` where `TABLE_NAME` = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE COLUMN_KEY EXTRA PRIVILEGES COLUMN_COMMENT STORAGE FORMAT select * from `information_schema`.`KEY_COLUMN_USAGE` where `TABLE_SCHEMA` = NULL; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION POSITION_IN_UNIQUE_CONSTRAINT REFERENCED_TABLE_SCHEMA REFERENCED_TABLE_NAME REFERENCED_COLUMN_NAME select * from `information_schema`.`KEY_COLUMN_USAGE` where `TABLE_NAME` = NULL; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION POSITION_IN_UNIQUE_CONSTRAINT REFERENCED_TABLE_SCHEMA REFERENCED_TABLE_NAME REFERENCED_COLUMN_NAME select * from `information_schema`.`PARTITIONS` where `TABLE_SCHEMA` = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PARTITION_NAME SUBPARTITION_NAME PARTITION_ORDINAL_POSITION SUBPARTITION_ORDINAL_POSITION PARTITION_METHOD SUBPARTITION_METHOD PARTITION_EXPRESSION SUBPARTITION_EXPRESSION PARTITION_DESCRIPTION TABLE_ROWS AVG_ROW_LENGTH DATA_LENGTH MAX_DATA_LENGTH INDEX_LENGTH DATA_FREE CREATE_TIME UPDATE_TIME CHECK_TIME CHECKSUM PARTITION_COMMENT NODEGROUP TABLESPACE_NAME select * from `information_schema`.`PARTITIONS` where `TABLE_NAME` = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME PARTITION_NAME SUBPARTITION_NAME PARTITION_ORDINAL_POSITION SUBPARTITION_ORDINAL_POSITION PARTITION_METHOD SUBPARTITION_METHOD PARTITION_EXPRESSION SUBPARTITION_EXPRESSION PARTITION_DESCRIPTION TABLE_ROWS AVG_ROW_LENGTH DATA_LENGTH MAX_DATA_LENGTH INDEX_LENGTH DATA_FREE CREATE_TIME UPDATE_TIME CHECK_TIME CHECKSUM PARTITION_COMMENT NODEGROUP TABLESPACE_NAME select * from `information_schema`.`REFERENTIAL_CONSTRAINTS` where `CONSTRAINT_SCHEMA` = NULL; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME UNIQUE_CONSTRAINT_CATALOG UNIQUE_CONSTRAINT_SCHEMA UNIQUE_CONSTRAINT_NAME MATCH_OPTION UPDATE_RULE DELETE_RULE TABLE_NAME REFERENCED_TABLE_NAME select * from `information_schema`.`REFERENTIAL_CONSTRAINTS` where `TABLE_NAME` = NULL; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME UNIQUE_CONSTRAINT_CATALOG UNIQUE_CONSTRAINT_SCHEMA UNIQUE_CONSTRAINT_NAME MATCH_OPTION UPDATE_RULE DELETE_RULE TABLE_NAME REFERENCED_TABLE_NAME select * from information_schema.schemata where schema_name = NULL; CATALOG_NAME SCHEMA_NAME DEFAULT_CHARACTER_SET_NAME DEFAULT_COLLATION_NAME SQL_PATH select * from `information_schema`.`STATISTICS` where `TABLE_SCHEMA` = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME NON_UNIQUE INDEX_SCHEMA INDEX_NAME SEQ_IN_INDEX COLUMN_NAME COLLATION CARDINALITY SUB_PART PACKED NULLABLE INDEX_TYPE COMMENT select * from `information_schema`.`STATISTICS` where `TABLE_NAME` = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME NON_UNIQUE INDEX_SCHEMA INDEX_NAME SEQ_IN_INDEX COLUMN_NAME COLLATION CARDINALITY SUB_PART PACKED NULLABLE INDEX_TYPE COMMENT select * from information_schema.tables where table_schema = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME TABLE_TYPE ENGINE VERSION ROW_FORMAT TABLE_ROWS AVG_ROW_LENGTH DATA_LENGTH MAX_DATA_LENGTH INDEX_LENGTH DATA_FREE AUTO_INCREMENT CREATE_TIME UPDATE_TIME CHECK_TIME TABLE_COLLATION CHECKSUM CREATE_OPTIONS TABLE_COMMENT select * from information_schema.tables where table_catalog = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME TABLE_TYPE ENGINE VERSION ROW_FORMAT TABLE_ROWS AVG_ROW_LENGTH DATA_LENGTH MAX_DATA_LENGTH INDEX_LENGTH DATA_FREE AUTO_INCREMENT CREATE_TIME UPDATE_TIME CHECK_TIME TABLE_COLLATION CHECKSUM CREATE_OPTIONS TABLE_COMMENT select * from information_schema.tables where table_name = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME TABLE_TYPE ENGINE VERSION ROW_FORMAT TABLE_ROWS AVG_ROW_LENGTH DATA_LENGTH MAX_DATA_LENGTH INDEX_LENGTH DATA_FREE AUTO_INCREMENT CREATE_TIME UPDATE_TIME CHECK_TIME TABLE_COLLATION CHECKSUM CREATE_OPTIONS TABLE_COMMENT select * from `information_schema`.`TABLE_CONSTRAINTS` where `TABLE_SCHEMA` = NULL; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_SCHEMA TABLE_NAME CONSTRAINT_TYPE select * from `information_schema`.`TABLE_CONSTRAINTS` where `TABLE_NAME` = NULL; CONSTRAINT_CATALOG CONSTRAINT_SCHEMA CONSTRAINT_NAME TABLE_SCHEMA TABLE_NAME CONSTRAINT_TYPE select * from `information_schema`.`TRIGGERS` where `EVENT_OBJECT_SCHEMA` = NULL; TRIGGER_CATALOG TRIGGER_SCHEMA TRIGGER_NAME EVENT_MANIPULATION EVENT_OBJECT_CATALOG EVENT_OBJECT_SCHEMA EVENT_OBJECT_TABLE ACTION_ORDER ACTION_CONDITION ACTION_STATEMENT ACTION_ORIENTATION ACTION_TIMING ACTION_REFERENCE_OLD_TABLE ACTION_REFERENCE_NEW_TABLE ACTION_REFERENCE_OLD_ROW ACTION_REFERENCE_NEW_ROW CREATED SQL_MODE DEFINER CHARACTER_SET_CLIENT COLLATION_CONNECTION DATABASE_COLLATION select * from `information_schema`.`TRIGGERS` where `EVENT_OBJECT_TABLE` = NULL; TRIGGER_CATALOG TRIGGER_SCHEMA TRIGGER_NAME EVENT_MANIPULATION EVENT_OBJECT_CATALOG EVENT_OBJECT_SCHEMA EVENT_OBJECT_TABLE ACTION_ORDER ACTION_CONDITION ACTION_STATEMENT ACTION_ORIENTATION ACTION_TIMING ACTION_REFERENCE_OLD_TABLE ACTION_REFERENCE_NEW_TABLE ACTION_REFERENCE_OLD_ROW ACTION_REFERENCE_NEW_ROW CREATED SQL_MODE DEFINER CHARACTER_SET_CLIENT COLLATION_CONNECTION DATABASE_COLLATION select * from `information_schema`.`VIEWS` where `TABLE_SCHEMA` = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME VIEW_DEFINITION CHECK_OPTION IS_UPDATABLE DEFINER SECURITY_TYPE CHARACTER_SET_CLIENT COLLATION_CONNECTION select * from `information_schema`.`VIEWS` where `TABLE_NAME` = NULL; TABLE_CATALOG TABLE_SCHEMA TABLE_NAME VIEW_DEFINITION CHECK_OPTION IS_UPDATABLE DEFINER SECURITY_TYPE CHARACTER_SET_CLIENT COLLATION_CONNECTION explain extended select 1 from information_schema.tables; id select_type table type possible_keys key key_len ref rows filtered Extra 1 SIMPLE tables ALL NULL NULL NULL NULL NULL NULL Skip_open_table; Scanned all databases Warnings: Note 1003 select 1 AS `1` from `information_schema`.`tables` use information_schema; show events; Db Name Definer Time zone Type Execute at Interval value Interval field Starts Ends Status Originator character_set_client collation_connection Database Collation show events from information_schema; Db Name Definer Time zone Type Execute at Interval value Interval field Starts Ends Status Originator character_set_client collation_connection Database Collation show events where Db= 'information_schema'; Db Name Definer Time zone Type Execute at Interval value Interval field Starts Ends Status Originator character_set_client collation_connection Database Collation use test; # # Bug#34166 Server crash in SHOW OPEN TABLES and prelocking # drop table if exists t1; drop function if exists f1; create table t1 (a int); create function f1() returns int begin insert into t1 (a) values (1); return 0; end| show open tables where f1()=0; show open tables where f1()=0; drop table t1; drop function f1; select * from information_schema.tables where 1=sleep(100000); select * from information_schema.columns where 1=sleep(100000); explain select count(*) from information_schema.tables; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE tables ALL NULL NULL NULL NULL NULL Skip_open_table; Scanned all databases explain select count(*) from information_schema.columns; id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE columns ALL NULL NULL NULL NULL NULL Open_frm_only; Scanned all databases 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=""; create table t0 select * from information_schema.global_status where VARIABLE_NAME='COM_SELECT'; SELECT 1; 1 1 select a.VARIABLE_VALUE - b.VARIABLE_VALUE from t0 b, information_schema.global_status a where a.VARIABLE_NAME = b.VARIABLE_NAME; a.VARIABLE_VALUE - b.VARIABLE_VALUE 2 drop table t0; CREATE TABLE t1(a INT) KEY_BLOCK_SIZE=1; SELECT CREATE_OPTIONS FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME='t1'; CREATE_OPTIONS KEY_BLOCK_SIZE=1 DROP TABLE t1; SET TIMESTAMP=@@TIMESTAMP + 10000000; SELECT 'OK' AS TEST_RESULT FROM INFORMATION_SCHEMA.PROCESSLIST WHERE time < 0; TEST_RESULT OK SET TIMESTAMP=DEFAULT; # # Bug #50276: Security flaw in INFORMATION_SCHEMA.TABLES # CREATE DATABASE db1; USE db1; CREATE TABLE t1 (id INT); CREATE USER nonpriv; USE test; # connected as nonpriv # Should return 0 SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME='t1'; COUNT(*) 0 USE INFORMATION_SCHEMA; # Should return 0 SELECT COUNT(*) FROM TABLES WHERE TABLE_NAME='t1'; COUNT(*) 0 # connected as root DROP USER nonpriv; DROP TABLE db1.t1; DROP DATABASE db1; Bug#54422 query with = 'variables' CREATE TABLE variables(f1 INT); SELECT COLUMN_DEFAULT, TABLE_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE INFORMATION_SCHEMA.COLUMNS.TABLE_NAME = 'variables'; COLUMN_DEFAULT TABLE_NAME NULL variables DROP TABLE variables; # # Bug #53814: NUMERIC_PRECISION for unsigned bigint field is 19, # should be 20 # CREATE TABLE ubig (a BIGINT, b BIGINT UNSIGNED); SELECT TABLE_NAME, COLUMN_NAME, NUMERIC_PRECISION FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME='ubig'; TABLE_NAME COLUMN_NAME NUMERIC_PRECISION ubig a 19 ubig b 20 INSERT INTO ubig VALUES (0xFFFFFFFFFFFFFFFF,0xFFFFFFFFFFFFFFFF); Warnings: Warning 1264 Out of range value for column 'a' at row 1 SELECT length(CAST(b AS CHAR)) FROM ubig; length(CAST(b AS CHAR)) 20 DROP TABLE ubig; End of 5.1 tests.