| mysql> SHOW STATUS LIKE 'Qcache%'; |
| +---------------+-------+ | Variable_name | Value | +---------------+-------+ | Qcache_hits | 1 | --表示sql在缓存中直接得到结果，不需要再去解析 +---------------+-------+ 8 rows in set (0.00 sec) |
| mysql> select count(*) from animals; |
| +----------+ | count(*) | +----------+ | 6 | +----------+ 1 row in set (0.00 sec) |
| mysql> select count(*) from animals; |
| +----------+ | count(*) | +----------+ | 6 | +----------+ 1 row in set (0.00 sec) |
| mysql> SHOW STATUS LIKE 'Qcache_hits'; |
| +---------------+-------+ | Variable_name | Value | +---------------+-------+ | Qcache_hits | 3 | --上面的sql也是是从缓存中直接取到结果 +---------------+-------+ 1 row in set (0.00 sec) |
| mysql> insert into animals select 9,'testsds' ; --插入数据后，跟这个表所有相关的sql缓存就会被清空掉 |
| Query OK, 1 row affected (0.00 sec) Records: 1 Duplicates: 0 Warnings: 0 |
| mysql> select count(*) from animals; |
| +----------+ | count(*) | +----------+ | 7 | +----------+ 1 row in set (0.00 sec) |
| mysql> SHOW STATUS LIKE 'Qcache_hits'; |
| +---------------+-------+ | Variable_name | Value | +---------------+-------+ | Qcache_hits | 3 | --还是等于3，说明上一条sql是没有直接从缓存中直接得到的 +---------------+-------+ 1 row in set (0.00 sec) |
| mysql> select count(*) from animals; |
| +----------+ | count(*) | +----------+ | 7 | +----------+ 1 row in set (0.00 sec) |
| mysql> SHOW STATUS LIKE 'Qcache_hits'; |
| +---------------+-------+ | Variable_name | Value | +---------------+-------+ | Qcache_hits | 4 | +---------------+-------+ 1 row in set (0.00 sec) |
