• mysql查看某张表、库的大小


    1、查询某张表的大小

    mysql >  select concat(round(sum(DATA_LENGTH/1024/1024),2),'M') from information_schema.tables where table_schema='test' AND table_name='t9'; 

    2、查看某个数据库表的数据

    [root@tst-yangsq2-2 ~]# mysqlshow -uroot -p --count test
    Enter password: 
    Database: test
    +--------+----------+------------+
    | Tables | Columns  | Total Rows |
    +--------+----------+------------+
    | t1     |        1 |          2 |
    | t2     |        1 |          2 |
    | t3     |        2 |          1 |
    | t4     |        1 |          6 |
    | t5     |        1 |          1 |
    | t6     |        1 |         14 |
    | t7     |        1 |          0 |
    | t8     |        1 |         12 |
    | t9     |        7 |      48147 |
    +--------+----------+------------+

    3、查询某个数据库某张表的数据 #类似于desc

    [root@tst-yangsq2-2 ~]# mysqlshow -uroot -p --count test t9
    Enter password: 
    Database: test  Table: t9  Rows: 48147
    +--------------+----------------------+-----------+------+-----+-------------------+-----------------------------+---------------------------------+---------+
    | Field        | Type                 | Collation | Null | Key | Default           | Extra                       | Privileges                      | Comment |
    +--------------+----------------------+-----------+------+-----+-------------------+-----------------------------+---------------------------------+---------+
    | payment_id   | smallint(5) unsigned |           | NO   |     |                   |                             | select,insert,update,references |         |
    | customer_id  | smallint(5) unsigned |           | NO   | MUL |                   |                             | select,insert,update,references |         |
    | staff_id     | tinyint(3) unsigned  |           | NO   | MUL |                   |                             | select,insert,update,references |         |
    | rental_id    | int(11)              |           | YES  | MUL |                   |                             | select,insert,update,references |         |
    | amount       | decimal(5,2)         |           | NO   |     |                   |                             | select,insert,update,references |         |
    | payment_date | datetime             |           | NO   |     |                   |                             | select,insert,update,references |         |
    | last_update  | timestamp            |           | YES  |     | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP | select,insert,update,references |         |
    +--------------+----------------------+-----------+------+-----+-------------------+-----------------------------+---------------------------------+---------+
     
     
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  • 原文地址:https://www.cnblogs.com/Knight7971/p/9963299.html
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