能在MySQL WHERE语句中使用SUM()函数的结果吗？

在MySQL中，可以使用HAVING子句而不是WHERE子句。让我们首先创建一个表 –

mysql> create table DemoTable
(
   Name varchar(50),
   Price int
);
Query OK, 0 rows affected (0.79 sec)

使用insert命令在表中插入一些记录 –

mysql> insert into DemoTable values('Chris',30);
Query OK, 1 row affected (0.15 sec)
mysql> insert into DemoTable values('David',40);
Query OK, 1 row affected (0.19 sec)
mysql> insert into DemoTable values('Chris',10);
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable values('Mike',44);
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable values('David',5);
Query OK, 1 row affected (0.17 sec)

使用select语句显示表中的所有记录 –

mysql> select *from DemoTable;

此操作将产生以下输出 –

+-------+-------+
| Name  | Price |
+-------+-------+
| Chris | 30    |
| David | 40    |
| Chris | 10    |
| Mike  | 44    |
| David | 5     |
+-------+-------+
5 rows in set (0.00 sec)

以下是在HAVING子句中使用SUM()函数结果的查询 –

mysql> select Name,SUM(Price) AS Total_Price from DemoTable group by Name having Total_Price > 40;

此操作将产生以下输出 –

+-------+-------------+
| Name  | Total_Price |
+-------+-------------+
| David | 45          |
| Mike  | 44          |
+-------+-------------+
2 rows in set (0.03 sec)

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