如何在MySQL中更改项目顺序？

要更改MySQL中项目的顺序，请使用ORDER BY别名。让我们首先创建一个表-

mysql> create table DemoTable653 (Product1Amount int,Product2Amount int);

使用插入命令在表中插入一些记录-

mysql> insert into DemoTable653 values(400,250);
mysql> insert into DemoTable653 values(500,300);
mysql> insert into DemoTable653 values(40,400);
mysql> insert into DemoTable653 values(200,450);
mysql> insert into DemoTable653 values(50,20);

使用select语句显示表中的所有记录-

mysql> select *from DemoTable653;

这将产生以下输出-

+----------------+----------------+
| Product1Amount | Product2Amount |
+----------------+----------------+
|            400 |            250 |
|            500 |            300 |
|            40  |            400 |
|            200 |            450 |
|            50  |             20 |
+----------------+----------------+
5 rows in set (0.00 sec)

以下是更改项目顺序并显示差异的查询-

mysql> select Product1Amount,Product2Amount,(Product1Amount-Product2Amount) as ProductAmountDifference from DemoTable653 order by ProductAmountDifference;

这将产生以下输出-

+----------------+----------------+-------------------------+
| Product1Amount | Product2Amount | ProductAmountDifference |
+----------------+----------------+-------------------------+
| 40             |            400 |                    -360 |
| 200            |            450 |                    -250 |
| 50             |             20 |                      30 |
| 400            |            250 |                     150 |
| 500            |            300 |                     200 |
+----------------+----------------+-------------------------+
5 rows in set (0.29 sec)