常用有效检测数据库运行状态SQL脚本

1、查看数据库中不为 InnoDB 引擎的表

 

SELECT TABLE_SCHEMA, TABLE_NAME, ENGINE

  FROM information_schema.TABLES

 WHERE TABLE_SCHEMA NOT IN

      ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

   AND ENGINE != 'InnoDB';

 

   

2、查看数据库中表的大小及数据量

 

SELECT TABLE_SCHEMA, TABLE_NAME, TABLE_ROWS,

       CONCAT(round((DATA_LENGTH + INDEX_LENGTH) / 1024 / 1024, 2), 'MB') as data

  FROM information_schema.TABLES

 WHERE TABLE_SCHEMA NOT IN 

       ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

 ORDER BY DATA_LENGTH + INDEX_LENGTH DESC;

 

 

3、查找数据库中无显式主键索引的表

 

SELECT t.TABLE_SCHEMA, t.TABLE_NAME

  FROM information_schema.TABLES t

 WHERE (t.TABLE_SCHEMA, t.TABLE_NAME) NOT IN

       (SELECT DISTINCT TABLE_SCHEMA, TABLE_NAME

          FROM information_schema.COLUMNS

         WHERE COLUMN_KEY = 'PRI')

   AND t.TABLE_SCHEMA NOT IN

       ('sys', 'mysql', 'performance_schema', 'information_schema', 'test');

 

    

4、查找数据库中主键为联合主键的表

 

SELECT TABLE_SCHEMA, TABLE_NAME,

       GROUP_CONCAT(COLUMN_NAME ORDER BY SEQ_IN_INDEX SEPARATOR ',') cols,

       MAX(SEQ_IN_INDEX) len

  FROM information_schema.STATISTICS

 WHERE INDEX_NAME = 'PRIMARY'

   AND TABLE_SCHEMA NOT IN

       ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

 GROUP BY TABLE_SCHEMA, TABLE_NAME

HAVING len > 1;

 

 

5、查找数据库中不为自增主键的表

 

SELECT TABLE_SCHEMA, TABLE_NAME

  FROM information_schema.TABLES

 WHERE TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

   AND (TABLE_SCHEMA,TABLE_NAME) NOT IN 

       (SELECT TABLE_SCHEMA, TABLE_NAME

          FROM information_schema.COLUMNS

         WHERE TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

           AND IS_NULLABLE = 'NO'

           AND COLUMN_TYPE LIKE '%int%'

           AND COLUMN_KEY = 'PRI'

           AND EXTRA = 'auto_increment');

 

     

6、查看数据库中存在外键约束的表

 

SELECT c.TABLE_SCHEMA,

       c.REFERENCED_TABLE_NAME,

       c.REFERENCED_COLUMN_NAME,

       c.TABLE_NAME,

       c.COLUMN_NAME,

       c.CONSTRAINT_NAME,

       t.TABLE_COMMENT,

       r.UPDATE_RULE,

       r.DELETE_RULE

  FROM information_schema.KEY_COLUMN_USAGE c

  JOIN information_schema.TABLES t

    ON t.TABLE_NAME = c.TABLE_NAME

  JOIN information_schema.REFERENTIAL_CONSTRAINTS r

    ON r.TABLE_NAME = c.TABLE_NAME

   AND r.CONSTRAINT_NAME = c.CONSTRAINT_NAME

   AND r.REFERENCED_TABLE_NAME = c.REFERENCED_TABLE_NAME

 WHERE c.REFERENCED_TABLE_NAME IS NOT NULL;

 

 

7、查找数据库中低区分度索引（区分度小于0.1）

 

SELECT p.TABLE_SCHEMA, p.TABLE_NAME, c.INDEX_NAME, c.car, p.car total

  FROM (SELECT TABLE_SCHEMA, TABLE_NAME, INDEX_NAME, MAX(CARDINALITY) car

          FROM information_schema.STATISTICS

         WHERE INDEX_NAME != 'PRIMARY'

           AND TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

         GROUP BY TABLE_SCHEMA, TABLE_NAME, INDEX_NAME) c

 INNER JOIN (SELECT TABLE_SCHEMA, TABLE_NAME, MAX(CARDINALITY) car

               from information_schema.STATISTICS

              WHERE INDEX_NAME = 'PRIMARY'

                AND TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

              GROUP BY TABLE_SCHEMA, TABLE_NAME) p

    ON c.TABLE_NAME = p.TABLE_NAME

   AND c.TABLE_SCHEMA = p.TABLE_SCHEMA

 WHERE p.car > 0

   AND c.car / p.car < 0.1;

 

   

8、查找数据库中重复索引前缀的索引

 

 SELECT a.TABLE_SCHEMA, a.TABLE_NAME, a.INDEX_NAME, a.cols, b.INDEX_NAME, b.cols

  FROM (SELECT TABLE_SCHEMA, TABLE_NAME, INDEX_NAME,

               CONCAT('| ', GROUP_CONCAT(COLUMN_NAME ORDER BY SEQ_IN_INDEX SEPARATOR ' | '), ' |') AS cols

          FROM information_schema.STATISTICS

         WHERE TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

           AND INDEX_NAME != 'PRIMARY'

         GROUP BY TABLE_SCHEMA, TABLE_NAME, INDEX_NAME) a

 INNER JOIN (SELECT TABLE_SCHEMA, TABLE_NAME, INDEX_NAME,

                    CONCAT('| ', GROUP_CONCAT(COLUMN_NAME ORDER BY SEQ_IN_INDEX SEPARATOR ' | '), ' |') AS cols

               FROM information_schema.STATISTICS

              WHERE TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

                AND INDEX_NAME != 'PRIMARY'

              GROUP BY TABLE_SCHEMA, TABLE_NAME, INDEX_NAME) b

    ON a.TABLE_NAME = b.TABLE_NAME

   AND a.TABLE_SCHEMA = b.TABLE_SCHEMA

   AND a.cols LIKE CONCAT(b.cols, '%')

   AND a.INDEX_NAME != b.INDEX_NAME;

 

   

9、查找数据库中包索引重复包含主键列的索引

 

SELECT a.*, b.pk

  FROM (SELECT TABLE_SCHEMA, TABLE_NAME, INDEX_NAME,

               CONCAT('| ', GROUP_CONCAT(COLUMN_NAME ORDER BY SEQ_IN_INDEX SEPARATOR ' | '), ' |') cols

          FROM information_schema.STATISTICS

         WHERE INDEX_NAME != 'PRIMARY'

           AND TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

         GROUP BY TABLE_SCHEMA, TABLE_NAME, INDEX_NAME) a

 INNER JOIN (SELECT TABLE_SCHEMA, TABLE_NAME,

                    CONCAT('| ', GROUP_CONCAT(COLUMN_NAME ORDER BY SEQ_IN_INDEX SEPARATOR ' | '), ' |') pk

               FROM information_schema.STATISTICS

              WHERE INDEX_NAME = 'PRIMARY'

                AND TABLE_SCHEMA NOT IN ('sys', 'mysql', 'performance_schema', 'information_schema', 'test')

              GROUP BY TABLE_SCHEMA, TABLE_NAME) b

    ON a.TABLE_NAME = b.TABLE_NAME

   AND a.TABLE_SCHEMA = b.TABLE_SCHEMA

   AND a.cols LIKE CONCAT('%', b.pk, '%');

 

   

10、查找数据库中没有被使用的索引

 

SELECT a.OBJECT_SCHEMA, a.OBJECT_NAME, a.INDEX_NAME, b.TABLE_ROWS

  FROM performance_schema.TABLE_IO_WAITS_SUMMARY_BY_INDEX_USAGE a

 INNER JOIN information_schema.TABLES b

    ON a.OBJECT_SCHEMA = b.TABLE_SCHEMA

   AND a.OBJECT_NAME = b.TABLE_SCHEMA

 WHERE a.INDEX_NAME IS NOT NULL

   AND a.INDEX_NAME != 'PRIMARY'

   AND a.COUNT_STAR = 0

   AND OBJECT_SCHEMA NOT IN

       ('sys', 'mysql', 'performance_schema', 'information_schema')

 ORDER BY OBJECT_SCHEMA, OBJECT_NAME;

  

  

11、查看数据库中的锁请求信息

 

SELECT r.TRX_ISOLATION_LEVEL,

       r.TRX_ID WAITING_TRX_ID,

       r.TRX_MYSQL_THREAD_ID WAITING_TRX_THREAD,

       r.TRX_STATE WAITING_TRX_STATE,

       lr.LOCK_MODE WAITING_TRX_LOCK_MODE,

       lr.LOCK_TYPE WAITING_TRX_LOCK_TYPE,

       lr.LOCK_TABLE WAITING_TRX_LOCK_TABLE,

       lr.LOCK_INDEX WAITING_TRX_LOCK_INDEX,

       r.TRX_QUERY WAITING_TRX_QUERY,

       b.TRX_ID BLOCKING_TRX_ID,

       b.TRX_MYSQL_THREAD_ID BLOCKING_TRX_THREAD,

       b.TRX_STATE BLOCKING_TRX_STATE,

       lb.LOCK_MODE BLOCKING_TRX_LOCK_MODE,

       lb.LOCK_TYPE BLOCKING_TRX_LOCK_TYPE,

       lb.LOCK_TABLE BLOCKING_TRX_LOCK_TABLE,

       lb.LOCK_INDEX BLOCKING_TRX_LOCK_INDEX,

       b.TRX_QUERY BLOCKING_QUERY

  FROM information_schema.INNODB_LOCK_WAITS w

 INNER JOIN INFORMATION_SCHEMA.INNODB_TRX b

    ON b.TRX_ID = W.BLOCKING_TRX_ID

 INNER JOIN information_schema.INNODB_TRX R

    ON r.TRX_ID = W.REQUESTING_TRX_ID

 INNER JOIN information_schema.INNODB_LOCKS lb

    ON lb.LOCK_TRX_ID = W.BLOCKING_TRX_ID

 INNER JOIN information_schema.INNODB_LOCKS lr

    ON lr.LOCK_TRX_ID = W.REQUESTING_TRX_ID;