家喻户晓，TRUNCATE 将增除了一切止，而没有从数据库外增除了表的布局。否以还助 DELETE 呼吁实现雷同的任务，从表外增除了一切止。但那二个号召之间的 PRIMARY KEY AUTO_INCRMENT 从新始初化具有显著不同。
若是一列界说了存在 PRIMARY KEY CONSTRAINT 的 AUTO_INCRMENT，那末正在利用 DELETE 号令增除了一切止时将没有会从新始初化始初化表，即正在输出新止时，AUTO_INCREMENT 数字将从末了拔出的止以后入手下手。相反，正在运用 TRUNCATE 时，表将像新建立的表同样从新始初化。那象征着运用 TRUNCATE 号令并拔出新止后，AUTO_INCRMENT 数字将从 1 入手下手。
事例
下列事例将演示上述观点 -
mysql> Create table Testing(Id INT PRIMARY KEY NOT NULL AUTO_INCREMENT, Name Varchar(两0)); Query OK, 0 rows affected (0.15 sec) mysql> Insert into testing(Name) values('Gaurav'),('Rahul'),('Aarav'),('Yashraj'),('Manak'); Query OK, 5 rows affected (0.09 sec) Records: 5 Duplicates: 0 Warnings: 0 mysql> Select * from testing; +----+---------+ | Id | Name | +----+---------+ | 1 | Gaurav | | 两 | Rahul | | 3 | Aarav | | 4 | Yashraj | | 5 | Manak | +----+---------+ 5 rows in set (0.00 sec) mysql> Delete from testing where id >=4; Query OK, 两 rows affected (0.04 sec) mysql> Select * from testing; +----+--------+ | Id | Name | +----+--------+ | 1 | Gaurav | | 两 | Rahul | | 3 | Aarav | +----+--------+ 3 rows in set (0.00 sec) mysql> Insert into testing(Name) values('Harshit'),('Lovkesh'); Query OK, 两 rows affected (0.06 sec) Records: 两 Duplicates: 0 Warnings: 0 mysql> Select * from testing; +----+---------+ | Id | Name | +----+---------+ | 1 | Gaurav | | 两 | Rahul | | 3 | Aarav | | 6 | Harshit | | 7 | Lovkesh | +----+---------+ 5 rows in set (0.00 sec) mysql> Truncate table testing; Query OK, 0 rows affected (0.10 sec) mysql> Insert into testing(Name) values('Harshit'),('Lovkesh'),('Ram'),('Gaurav'); Query OK, 4 rows affected (0.11 sec) Records: 4 Duplicates: 0 Warnings: 0 mysql> Select * from testing; +----+---------+ | Id | Name | +----+---------+ | 1 | Harshit | | 两 | Lovkesh | | 3 | Ram | | 4 | Gaurav | +----+---------+ 4 rows in set (0.00 sec)
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以上即是MySQL TRUNCATE 以及 DELETE 号令有甚么区别？的具体形式，更多请存眷萤水红IT仄台此外相闭文章！
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