使用MySQL IF语句更新表中的多个值

让我们首先创建一个表-

create table DemoTable716 (
   Id varchar(100),
   Value1 int,
   Value2 int,
   Value3 int
);

使用插入命令在表中插入一些记录-

insert into DemoTable716 values('100',45,86,79);
insert into DemoTable716 values('101',67,67,99);
insert into DemoTable716 values('102',77,57,98);
insert into DemoTable716 values('103',45,67,92);

使用select语句显示表中的所有记录-

select *from DemoTable716;

这将产生以下输出-

+------+--------+--------+--------+
| Id   | Value1 | Value2 | Value3 |
+------+--------+--------+--------+
| 100  | 45     | 86     | 79     |
| 101  | 67     | 67     | 99     |
| 102  | 77     | 57     | 98     |
| 103  | 45     | 67     | 92     |
+------+--------+--------+--------+
4 rows in set (0.00 sec)

以下是更新表中多个值的查询-

update DemoTable716
   set Value3=if(Value1=67 OR Value2=67,67,NULL) where Id='101';
Rows matched: 1 Changed: 1 Warnings: 0

让我们再次检查表记录-

select *from DemoTable716;

这将产生以下输出-

+------+--------+--------+--------+
| Id   | Value1 | Value2 | Value3 |
+------+--------+--------+--------+
| 100  | 45     | 86     | 79     |
| 101  | 67     | 67     | 67     |
| 102  | 77     | 57     | 98     |
| 103  | 45     | 67     | 92     |
+------+--------+--------+--------+
4 rows in set (0.00 sec)