MySQL 如何使用单个WHERE子句更新多行

为此，您可以使用MySQL IN()。让我们首先创建一个 –

mysql> create table DemoTable1420
   -> (
   -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,
   -> FirstName varchar(20),
   -> LastName varchar(20),
   -> Age int
   -> );
Query OK, 0 rows affected (1.12 sec)

使用insert插入一些记录到该表中 –

mysql> insert into DemoTable1420(FirstName,LastName,Age) values('Chris','Brown',23);
Query OK, 1 row affected (0.16 sec)
mysql> insert into DemoTable1420(FirstName,LastName,Age) values('David','Miller',22);
Query OK, 1 row affected (0.19 sec)
mysql> insert into DemoTable1420(FirstName,LastName,Age) values('John','Smith',24);
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable1420(FirstName,LastName,Age) values('John','Doe',21);
Query OK, 1 row affected (0.43 sec)
mysql> insert into DemoTable1420(FirstName,LastName,Age) values('Adam','Smith',25);
Query OK, 1 row affected (0.18 sec)

使用select从表中显示所有记录 –

mysql> select * from DemoTable1420;

这将产生以下输出 –

+----+-----------+----------+------+
| Id | FirstName | LastName | Age  |
+----+-----------+----------+------+
|  1 | Chris     | Brown    |   23 |
|  2 | David     | Miller   |   22 |
|  3 | John      | Smith    |   24 |
|  4 | John      | Doe      |   21 |
|  5 | Adam      | Smith    |   25 |
+----+-----------+----------+------+
5 rows in set (0.00 sec)

以下是使用单个where子句更新多行的查询 –

mysql> update DemoTable1420
   -> set FirstName='Carol',LastName='Taylor'
   -> where Id IN(1,3,4,5);
Query OK, 4 rows affected (0.42 sec)
Rows matched: 4  Changed: 4 Warnings: 0

让我们再次检查表记录 –

mysql> select * from DemoTable1420;

这将产生以下输出 –

+----+-----------+----------+------+
| Id | FirstName | LastName | Age  |
+----+-----------+----------+------+
|  1 | Carol     | Taylor   | 23   |
|  2 | David     | Miller   | 22   |
|  3 | Carol     | Taylor   | 24   |
|  4 | Carol     | Taylor   | 21   |
|  5 | Carol     | Taylor   | 25   |
+----+-----------+----------+------+
5 rows in set (0.00 sec)

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