查看MySQL中的对象

Posted 2020-10-28

表：

 select TABLE_SCHEMA,TABLE_NAME,TABLE_TYPE,ENGINE from information_schema.tables where TABLE_SCHEMA not in ('performance_schema','information_schema','mysql');

 

视图：

 select TABLE_SCHEMA,TABLE_NAME  from information_schema.tables where table_type='view';

 

索引： 

SELECT TABLE_SCHEMA,TABLE_NAME,INDEX_NAME,INDEX_TYPE FROM INFORMATION_SCHEMA.STATISTICS  ;

存储过程：

 select  db,name  from  mysql.proc ;

函数：

select   *  from  mysql.func

事件：

select  db,name  from  mysql.event;

触发器：

 select TRIGGER_SCHEMA,TRIGGER_NAME from  information_schema.`TRIGGERS`;

 

约束

select TABLE_SCHEMA,TABLE_NAME,CONSTRAINT_NAME,CONSTRAINT_TYPE from  information_schema.`TABLE_CONSTRAINTS`;

外键：

select CONSTRAINT_SCHEMA, TABLE_NAME, CONSTRAINT_NAME, REFERENCED_TABLE_NAME from `information_schema`.REFERENTIAL_CONSTRAINTS ;

判断所有的表是否有主键：

SELECT

TABLE_SCHEMA,table_name 

FROM

    information_schema.TABLES

WHERE

    table_schema not in ('information_schema','performance_schema','sys','mysql')  AND

 TABLE_NAME NOT IN (

    SELECT

        table_name

    FROM

        information_schema.table_constraints t

    JOIN information_schema.key_column_usage k USING (

        constraint_name,

        table_schema,

        table_name

    )

    WHERE

        t.constraint_type = 'PRIMARY KEY'

      AND t.table_schema not in ('information_schema','performance_schema','sys','mysql')

);

统计MySQL数据库的数据量

SELECT  TABLE_SCHEMA,TABLE_NAME,ENGINE,TABLE_ROWS,AVG_ROW_LENGTH,concat(ROUND(DATA_LENGTH/1024/1024/1024,2),'G') "DATA_LENGTH" ,concat(ROUND(INDEX_LENGTH/1024/1024/1024,2),'G') "INDEX_LENGTH",concat(ROUND((INDEX_LENGTH/1024/1024/1024)+(DATA_LENGTH/1024/1024/1024),2),'G') "Total",TABLE_COLLATION,CREATE_TIME FROM

INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'xxx' ORDER BY TABLE_ROWS DESC;