mysqltruncate分区自定义参数
MySQL truncate table语句的使用Truncate table语句用来删除/截断表里的所有数据
- 和delete删除所有表数据在逻辑上含义相同,但性能更快
- 类似执行了drop table和create table两个语句
执行代码
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mysql> select * from students_bak; + -----+----------+--------+---------+ | sid | sname | gender | dept_id | + -----+----------+--------+---------+ | 101 | zhangsan | male | 10 | | 1 | aa | 1 | 1 | + -----+----------+--------+---------+ 2 rows in set (0.00 sec) mysql> truncate table students_bak; Query OK, 0 rows affected (0.16 sec) mysql> select * from students_bak; Empty set (0.00 sec) mysql> set autocommit= off ; Query OK, 0 rows affected (0.01 sec) mysql> select * from students3; + -----+-------+--------+---------+--------+ | sid | sname | gender | dept_id | sname2 | + -----+-------+--------+---------+--------+ | 100 | NULL | 1 | 1 | NULL | + -----+-------+--------+---------+--------+ 1 row in set (0.01 sec) mysql> truncate table students3; Query OK, 0 rows affected (0.06 sec) mysql> rollback ; Query OK, 0 rows affected (0.00 sec) mysql> select * from students3; Empty set (0.00 sec) mysql> delete from students; Query OK, 5 rows affected (0.00 sec) mysql> select * from students; Empty set (0.00 sec) mysql> rollback ; Query OK, 0 rows affected (0.07 sec) mysql> select * from students; + -----+-------+--------+---------+ | sid | sname | gender | dept_id | + -----+-------+--------+---------+ | 1 | aa | 3 | 1 | | 4 | cc | 3 | 1 | | 5 | dd | 1 | 2 | | 6 | aac | 1 | 1 | | 10 | a | 1 | 1 | + -----+-------+--------+---------+ 5 rows in set (0.00 sec) |
truncate需要什么权限
truncate的执行是先drop后create的, 所以truncate包含drop和create,是一个复合的动作, 对于create不用赋予, 所以只需要赋予drop权限就可以了
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原文链接:https://www.cnblogs.com/dinghailong128/p/12715904.html