查看mysql 数据表的真实大小空间情况

select count(*) from t1;

+----------+

| count(*) |

+----------+

|        5 |

+----------+

SELECT table_name,

data_length/1024/1024 AS ‘data_length(MB)‘,

index_length/1024/1024 AS ‘index_length(MB)‘,

(data_length + index_length)/1024/1024 AS ‘total(MB)‘

FROM information_schema.tables

WHERE table_schema=‘test‘

AND table_name = ‘t1‘;

+------------+-----------------+------------------+------------+

| table_name | data_length(MB) | index_length(MB) | total(MB)  |

+------------+-----------------+------------------+------------+

| t1        0.01562500    |    0.00000000 | 0.01562500 |

+------------+-----------------+------------------+------------+

从上面可以看出在磁盘上的数据大小是12G，而实际的大小才0.01562500MB(估计值)，在种情况使用逻辑迁移是再好不过的了。

防止伪大表出现。