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;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 | +------------------+-------+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;+--------------------+| @@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-> ;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 | | 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%';+-------------------------+-------+| Variable_name | Value |+-------------------------+-------+| Qcache_queries_in_cache | 1 | +-------------------------+-------+1 row in set (0.00 sec)MySQL> show status like 'qcache_f%';+--------------------+----------+| Variable_name | Value |+--------------------+----------+| 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。