mysql5.6中必要的存储引擎

mysql> select version();

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

| version() |

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

| 5.6.12 |

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

1 row in set (0.00 sec)

源码方式安装的Mysql5.6中默认支持如下几种存储引擎，其中InnoDB是默认的存储引擎。

mysql> show engines;

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

| Engine | Support | Comment | Transactions | XA | Savepoints |

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

| MEMORY | YES | Hash based, stored in memory, useful for temporary tables | NO | NO | NO |

| CSV | YES | CSV storage engine | NO | NO | NO |

| MyISAM | YES | MyISAM storage engine | NO | NO | NO |

| BLACKHOLE | YES | /dev/null storage engine (anything you write to it disappears) | NO | NO | NO |

| MRG_MYISAM | YES | Collection of identical MyISAM tables | NO | NO | NO |

| FEDERATED | NO | Federated MySQL storage engine | NULL | NULL | NULL |

| ARCHIVE | YES | Archive storage engine | NO | NO | NO |

| InnoDB | DEFAULT | Supports transactions, row-level locking, and foreign keys | YES | YES | YES |

| PERFORMANCE_SCHEMA | YES | Performance Schema | NO | NO | NO |

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

有些存储引擎暂时用不到，在编译的时候可以忽略掉。但那些存储引擎是必不可少的呢？

我们看到如下5种存储引擎是mysql自带的schema中使用到的。即便是在编译时指定忽略了某种存储引擎如：

-DWITHOUT_CSV_STORAGE_ENGINE=1 在安装后用show engines还是可以看到mysql支持CSV存储引擎。

mysql> select distinct TABLE_SCHEMA ,engine from information_schema.`TABLES`;

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

| TABLE_SCHEMA | engine |

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

| information_schema | MEMORY |

| information_schema | MyISAM |

| mysql | MyISAM |

| mysql | CSV |

| mysql | InnoDB |

| performance_schema | PERFORMANCE_SCHEMA |

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

因为在mysql这个schema中general_log, slow_log默认使用的是CSV存储引擎。

mysql> SELECT TABLE_SCHEMA ,TABLE_NAME ,ENGINE FROM information_schema.`TABLES` WHERE ENGINE='CSV';

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

| TABLE_SCHEMA | TABLE_NAME | ENGINE |

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

| mysql | general_log | CSV |

| mysql | slow_log | CSV |

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

2 rows in set (0.01 sec)

mysql> show engines;

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

| Engine | Support | Comment | Transactions | XA | Savepoints |

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

| CSV | YES | CSV storage engine | NO | NO | NO |

| InnoDB | DEFAULT | Supports transactions, row-level locking, and foreign keys | YES | YES | YES |

| MRG_MYISAM | YES | Collection of identical MyISAM tables | NO | NO | NO |

| PERFORMANCE_SCHEMA | YES | Performance Schema | NO | NO | NO |

| MyISAM | YES | MyISAM storage engine | NO | NO | NO |

| MEMORY | YES | Hash based, stored in memory, useful for temporary tables | NO | NO | NO |

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

6 rows in set (0.00 sec)