sql 基础--mysql 5 （10）

17.更新和删除数据

更新： update table set columns = ‘value’ where ...

mysql> update pw_price set price=10000 where uid=6;
Query OK, 1 row affected (0.03 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from pw_price;
+-----+-------+------------+
| uid | price | first_name |
+-----+-------+------------+
|   1 |   100 | wang       |
|   2 |  1000 | zhang      |
|   3 |  2000 | li         |
|   4 |  5000 | weizhi     |
|   5 |  5000 | cai        |
|   6 | 10000 | guo        |
+-----+-------+------------+
6 rows in set (0.00 sec)

mysql> update pw_price set first_name="guo6" where uid = 6;
Query OK, 1 row affected (0.03 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select * from pw_price;
+-----+-------+------------+
| uid | price | first_name |
+-----+-------+------------+
|   1 |   100 | wang       |
|   2 |  1000 | zhang      |
|   3 |  2000 | li         |
|   4 |  5000 | weizhi     |
|   5 |  5000 | cai        |
|   6 | 10000 | guo6       |
+-----+-------+------------+
6 rows in set (0.00 sec)

删除数据

delete from table where 。。。

mysql> select * from pw_price;
+-----+-------+------------+
| uid | price | first_name |
+-----+-------+------------+
|   1 |   100 | wang       |
|   2 |  1000 | zhang      |
|   3 |  2000 | li         |
|   4 |  5000 | weizhi     |
|   5 |  5000 | cai        |
|   6 | 10000 | guo6       |
+-----+-------+------------+
6 rows in set (0.00 sec)

mysql> delete from pw_price where uid >=6;
Query OK, 1 row affected (0.03 sec)

mysql> select * from pw_price;
+-----+-------+------------+
| uid | price | first_name |
+-----+-------+------------+
|   1 |   100 | wang       |
|   2 |  1000 | zhang      |
|   3 |  2000 | li         |
|   4 |  5000 | weizhi     |
|   5 |  5000 | cai        |
+-----+-------+------------+
5 rows in set (0.00 sec)

时间： 2024-10-13 21:43:38

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