MySQL数据库查看表占用空间大小及碎片整理

查询数据库所占空间

select concat(round(sum(data_length/1024/1024),2),'MB') as data from

information_schema.tables

where table_schema='dbName';

查询表所占空间

1 2	`select` `concat(round(sum(data_length/1024/1024),2),'MB')` `as` `data` `from` `information_schema.tables` `where` `table_schema='dbName'` `and` `table_name='tableName';`

查询数据库所有表所占空间

1 2	`select` `concat(round(sum(data_length/1024/1024),2),'MB')` `as` `data,table_name` `from` `information_schema.tables` `where` `table_schema='dbName'` `GROUP` `BY` `table_name` `ORDER` `BY` `data` `desc;`

查看所有数据库容量大小

select table_schema as '数据库名称',

sum(table_rows) as '记录数',

sum(truncate(data_length/1024/1024, 2)) as '数据容量(MB)',

sum(truncate(index_length/1024/1024, 2)) as '索引容量(MB)'

from information_schema.tables

group by table_schema

order by sum(data_length) desc, sum(index_length) desc;

查看所有数据库各表容量大小

select table_schema as '数据库名称',table_name as '表名',table_rows as '记录数',

truncate(data_length/1024/1024, 2) as '数据容量(MB)',

truncate(index_length/1024/1024, 2) as '索引容量(MB)'

from information_schema.tables

order by data_length desc, index_length desc;

查看指定数据库容量大小

select table_schema as '数据库名称',sum(table_rows) as '记录数',

sum(truncate(data_length/1024/1024, 2)) as '数据容量(MB)',sum(truncate(index_length/1024/1024, 2)) as '索引容量(MB)'

from information_schema.tables

where table_schema='dbName';

查看指定数据库各表容量大小

select table_schema as '数据库名称',table_name as '表名',table_rows as '记录数',truncate(data_length/1024/1024, 2) as '数据容量(MB)',truncate(index_length/1024/1024, 2) as '索引容量(MB)'

from information_schema.tables

where table_schema='dbName'

order by data_length desc, index_length desc;

mysql数据库整理碎片方法：

查看碎片方法

select table_schema db, table_name, data_free, engine

from information_schema.tables

where table_schema not in ('information_schema', 'mysql') and data_free > 0;

清除表碎片

方法1 alter table 表名 engine=InnoDB

alter table tableName engine=InnoDB;

#方法2 optimize table 表名

optimize table tableName;