在MySQL数据库中常用的引擎有两种：MyISAM和InnoDB。其他的还有BLOCKHOLE、CSV、MEMORY、Archive

MySQL数据库引擎
mysql数据库引擎常用面试总结
MySQL的InnoDB原理详解
B+Tree index structures in InnoDB

什么是存储引擎

MySQL中的数据用各种不同的技术存储在文件（或者内存）中。这些技术中的每一种技术都使用不同的存储机制、索引技巧、锁定水平,并且最终提供广泛的、不同的功能和能力。通过选择不同的技术，能够获得额外的速度或者功能，从而改善应用的整体功能。

• 不同的存储方式使用不同的存储技巧
• 不同的存储方式带来不同的性能体验

常用的存储引擎

存储引擎主要有：

• MyIsam
• InnoDB
• Mrg_Myisam
• Memory
• Blackhole
• CSV
• Performance_Schema
• Archive
• Federated

怎么查看MySQL数据库引擎

mysql>  show engines;

image.png

或者带上参数G

mysql>  show engines\G;

*************************** 1. row ***************************
      Engine: InnoDB
     Support: DEFAULT
     Comment: Supports transactions, row-level locking, and foreign keys
Transactions: YES
          XA: YES
  Savepoints: YES
*************************** 2. row ***************************
      Engine: MRG_MYISAM
     Support: YES
     Comment: Collection of identical MyISAM tables
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 3. row ***************************
      Engine: MEMORY
     Support: YES
     Comment: Hash based, stored in memory, useful for temporary tables
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 4. row ***************************
      Engine: BLACKHOLE
     Support: YES
     Comment: /dev/null storage engine (anything you write to it disappears)
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 5. row ***************************
      Engine: MyISAM
     Support: YES
     Comment: MyISAM storage engine
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 6. row ***************************
      Engine: CSV
     Support: YES
     Comment: CSV storage engine
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 7. row ***************************
      Engine: ARCHIVE
     Support: YES
     Comment: Archive storage engine
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 8. row ***************************
      Engine: PERFORMANCE_SCHEMA
     Support: YES
     Comment: Performance Schema
Transactions: NO
          XA: NO
  Savepoints: NO
*************************** 9. row ***************************
      Engine: FEDERATED
     Support: NO
     Comment: Federated MySQL storage engine
Transactions: NULL
          XA: NULL
  Savepoints: NULL
9 rows in set (0.00 sec)

ERROR: 
No query specified

• 查看创建表时的引擎
  MySQL5.6之后默认的引擎是InnoDB：show create table student;
  

  image.png

• 创建表时直接指定引擎

mysql> create table test (name varchar(20)) ENGINE=MyIsam;
Query OK, 0 rows affected (0.01 sec)

# 查看索引
mysql> show create table test;
+-------+----------------------------------------------------------------------------------------------+
| Table | Create Table                                                                                 |
+-------+----------------------------------------------------------------------------------------------+
| test  | CREATE TABLE `test` (
  `name` varchar(20) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8 |
+-------+----------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

• 如果不指定，默认是InnoDB
  
  image.png

MyIsam 和InnoDB对比