http://blog.163.com/freestyle_le/blog/static/1832794482011713103747931/
use information_schema
mysql> show tables; +---------------------------------------+ | Tables_in_information_schema | +---------------------------------------+ | CHARACTER_SETS | | CLIENT_STATISTICS | | COLLATIONS | | COLLATION_CHARACTER_SET_APPLICABILITY | | COLUMNS | | COLUMN_PRIVILEGES | | INDEX_STATISTICS | | ENGINES | | EVENTS | | FILES | | GLOBAL_STATUS | | GLOBAL_TEMPORARY_TABLES | | GLOBAL_VARIABLES | | KEY_COLUMN_USAGE | | PARAMETERS | | PARTITIONS | | PLUGINS | | PROCESSLIST | | PROFILING | | REFERENTIAL_CONSTRAINTS | | ROUTINES | | QUERY_RESPONSE_TIME | | SCHEMATA | | SCHEMA_PRIVILEGES | | SESSION_STATUS | | SESSION_VARIABLES | | STATISTICS | | TABLES | | TABLESPACES | | TABLE_CONSTRAINTS | | TABLE_PRIVILEGES | | TABLE_STATISTICS | | TEMPORARY_TABLES | | THREAD_STATISTICS | | TRIGGERS | | USER_PRIVILEGES | | USER_STATISTICS | | VIEWS | | INNODB_SYS_COLUMNS | | INNODB_RSEG | | INNODB_CMP | | INNODB_TRX | | INNODB_SYS_TABLESTATS | | INNODB_LOCK_WAITS | | XTRADB_ADMIN_COMMAND | | INNODB_LOCKS | | INNODB_SYS_FOREIGN_COLS | | INNODB_CMP_RESET | | INNODB_BUFFER_POOL_PAGES | | INNODB_SYS_TABLES | | INNODB_BUFFER_POOL_PAGES_INDEX | | INNODB_CMPMEM | | INNODB_BUFFER_POOL_PAGES_BLOB | | INNODB_CMPMEM_RESET | | INNODB_SYS_FIELDS | | INNODB_TABLE_STATS | | INNODB_SYS_STATS | | INNODB_SYS_FOREIGN | | INNODB_SYS_INDEXES | | INNODB_INDEX_STATS | +---------------------------------------+
1、KEY_COLUMN_USAGE表：描述了具有约束的键列。
select * from KEY_COLUMN_USAGE limit 10; +--------------------+-------------------+-----------------+---------------+--------------+-----------------------------------------+-----------------------------------------+------------------+-------------------------------+-------------------------+-----------------------+------------------------+ | 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 | +--------------------+-------------------+-----------------+---------------+--------------+-----------------------------------------+-----------------------------------------+------------------+-------------------------------+-------------------------+-----------------------+------------------------+ | def | control_stat | PRIMARY | def | control_stat | t_menu | pk_menu | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_result_control_playerflowrate_current | pk_control_current | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_result_control_playerflowrate_detail | pk_control_detail | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_result_control_playerflowrate_history | pk_control_history | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_result_js_error_detail | pk_result_js_error_detail | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_result_web_plugin_send_speed_current | pk_result_web_plugin_send_speed_current | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_result_web_plugin_system_current | pk_result_web_plugin_system_current | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_role | pk_role | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_role_menu | pk_role_menu | 1 | NULL | NULL | NULL | NULL | | def | control_stat | PRIMARY | def | control_stat | t_user | pk_user | 1 | NULL | NULL | NULL | NULL | +--------------------+-------------------+-----------------+---------------+--------------+-----------------------------------------+-----------------------------------------+------------------+-------------------------------+-------------------------+-----------------------+------------------------+ 10 rows in set (6.44 sec)
2、STATISTICS表：给出了关于表索引的信息。
mysql> select * from STATISTICS limit 10; +---------------+--------------+-----------------------------------------+------------+--------------+-----------------------------------------------------+--------------+--------------------+-----------+-------------+----------+--------+----------+------------+---------+---------------+ | 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 | INDEX_COMMENT | +---------------+--------------+-----------------------------------------+------------+--------------+-----------------------------------------------------+--------------+--------------------+-----------+-------------+----------+--------+----------+------------+---------+---------------+ | def | control_stat | t_menu | 0 | control_stat | PRIMARY | 1 | pk_menu | A | 9 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_current | 0 | control_stat | PRIMARY | 1 | pk_control_current | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_current | 1 | control_stat | i_result_control_playerflowrate_current_roomid | 1 | roomid | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_current | 1 | control_stat | i_result_control_playerflowrate_current_asnid | 1 | asnid | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_current | 1 | control_stat | i_result_control_playerflowrate_current_provinceid | 1 | provinceid | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_detail | 0 | control_stat | PRIMARY | 1 | pk_control_detail | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_detail | 1 | control_stat | t_result_control_playerflowrate_detail_roomid | 1 | roomid | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_detail | 1 | control_stat | t_result_control_playerflowrate_detail_provinceid | 1 | provinceid | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_detail | 1 | control_stat | t_result_control_playerflowrate_detail_asn | 1 | asn | A | 0 | NULL | NULL | | BTREE | | | | def | control_stat | t_result_control_playerflowrate_detail | 1 | control_stat | idx_result_control_playerflowrate_detail_min_roomid | 1 | minutecol | A | 0 | NULL | NULL | | BTREE | | | +---------------+--------------+-----------------------------------------+------------+--------------+-----------------------------------------------------+--------------+--------------------+-----------+-------------+----------+--------+----------+------------+---------+---------------+