删除表中的数据

MySQL从小白到总裁完整教程目录:https://blog.csdn.net/weixin_67859959/article/details/129334507?spm=1001.2014.3001.5502

语法格式:

delete from 表名 where 记录匹配条件;

说明：如果**不写where**子句，表示无条件，删除表中的**所有记录**（行）！

​          delete   删除

​          from   来自、对于

案列:删除test03表中，姓名(name)是rose的记录  

mysql> delete from test03 where name='rose';
Query OK, 1 row affected (0.05 sec)
 
mysql> select * from test03;
+------+------+--------+------------+---------+
| name | age  | salary | etime      | address |
+------+------+--------+------------+---------+
| king |   20 | 999.00 | 2022-01-01 | NULL    |
| tom  |   23 | 999.00 | 2022-01-01 | 广州    |
| Mary |   19 | 777.00 | 2022-01-01 | NULL    |
| lucy |   21 |  88.00 | 2022-01-01 | 上海    |
+------+------+--------+------------+---------+
4 rows in set (0.00 sec)

Query OK, 1 row affected (0.00 sec)
          1 行   被影响了！ 

练习：删除test01中，编号(id)是102的记录  

mysql> select * from test01;
+------+------+------+
| id   | name | age  |
+------+------+------+
|  101 | rose |   20 |
|  102 | Jack |   25 |
+------+------+------+
2 rows in set (0.00 sec)
 
mysql> delete from test01 where id=102;
Query OK, 1 row affected (0.00 sec)
 
mysql> select * from test01;
+------+------+------+
| id   | name | age  |
+------+------+------+
|  101 | rose |   20 |
+------+------+------+
1 row in set (0.00 sec)

 练习：删除test03表中的所有记录

mysql> delete from test03;
Query OK, 4 rows affected (0.02 sec)
 
mysql> select * from test03;
Empty set (0.00 sec)

 提示：Query OK, 4 rows affected (0.00 sec)
          4 行    被影响了

提示：Empty set (0.00 sec)  空的集合，就是没有数据