要将varchar转换为无符号整数,请使用CAST()
函数。让我们首先创建一个表-
mysql> create table DemoTable868(Amount varchar(100));
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable868 values('781'); mysql> insert into DemoTable868 values('990'); mysql> insert into DemoTable868 values('1002'); mysql> insert into DemoTable868 values('560'); mysql> insert into DemoTable868 values('890'); mysql> insert into DemoTable868 values('9890'); mysql> insert into DemoTable868 values('8723');
使用select语句显示表中的所有记录-
mysql> select *from DemoTable868;
这将产生以下输出-
+--------+ | Amount | +--------+ | 781 | | 990 | | 1002 | | 560 | | 890 | | 9890 | | 8723 | +--------+ 7 rows in set (0.00 sec)
以下是将varchar转换为无符号整数的查询-
mysql> select cast(Amount as unsigned) AS Amount from DemoTable868 order by Amount DESC;
这将产生以下输出-
+--------+ | Amount | +--------+ | 9890 | | 8723 | | 1002 | | 990 | | 890 | | 781 | | 560 | +--------+ 7 rows in set (0.01 sec)