MySQL 查询缓存的实际应用代码示例

以下的文章主要介绍的是MySQL 查询缓存的实际应用代码以及查看MySQL 查询缓存的大小 ，碎片整理，清除缓存以及监视MySQL 查询缓存性能的相关内容的描述，以下就是具体内容的描述，希望在你今后的学习中会有所帮助。

MySQL> select @@query_cache_type;

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

| @@query_cache_type |

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

| ON |

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

MySQL> set query_cache_type=off;

MySQL> set query_cache_type=on; php100.Com

MySQL>

MySQL> select sql_cache id, title, body from article;

MySQL> select sql_no_cache id, title, body from article;

MySQL> show variables like 'have_query_cache';

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

| Variable_name | Value |

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

| have_query_cache | YES |

+------------------+-------+ phP100.Com

1 row in set (0.00 sec)

查看MySQL 查询缓存的大小

MySQL> select @@global.query_cache_size;

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

| @@global.query_cache_size |

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

| 16777216 |

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

1 row in set (0.00 sec)

MySQL> select @@query_cache_size;

+--------------------+ phP100.Com

| @@query_cache_size |

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

| 16777216 |

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

1 row in set (0.00 sec)

查看最大缓存结果，如果结果集大于该数，不缓存。

MySQL> select @@global.query_cache_limit;

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

| @@global.query_cache_limit |

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

| 1048576 |

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

1 row in set (0.00 sec)

碎片整理

MySQL> flush query cache

-> ;

Query OK, 0 rows affected (0.00 sec)

清除缓存

MySQL> reset query cache phP100.Com

-> ;

Query OK, 0 rows affected (0.00 sec

监视MySQL 查询缓存性能：

MySQL> flush tables;

Query OK, 0 rows affected (0.04 sec)

MySQL> show status like 'qcache％';

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

| Variable_name | Value |

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

| Qcache_free_blocks | 1 |

| Qcache_free_memory | 16768408 |

| Qcache_hits | 6 |

| Qcache_inserts | 36 | PhP100.Com

| Qcache_lowmem_prunes | 0 |

| Qcache_not_cached | 86 |

| Qcache_queries_in_cache | 0 |

| Qcache_total_blocks | 1 |

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

8 rows in set (0.06 sec)

看看当前缓存中有多少条信息：

MySQL> show status like 'qcache_q％';

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

| Variable_name | Value |

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

| Qcache_queries_in_cache | 0 |

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

1 row in set (0.00 sec)

MySQL> select sql_cache id, title, body from article;

MySQL> show status like 'qcache_q％'; PhP100.Com

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

| Variable_name | Value |

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

| Qcache_queries_in_cache | 1 |

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

1 row in set (0.00 sec)

MySQL> show status like 'qcache_f％';

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

| Variable_name | Value |

+--------------------+----------+ PhP100.cOm

| Qcache_free_blocks | 1 |

| Qcache_free_memory | 16766728 |

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

2 rows in set (0.00 sec)

以上的相关内容就是对MySQL 查询缓存的介绍，望你能有所收获。