该Sum()
是在MySQL聚合函数。您可以将和查询与if条件一起使用。要了解带有if条件的求和查询,让我们创建一个表。
创建表的查询-
mysql> create table SumWithIfCondition −> ( −> ModeOfPayment varchar(100) −> , −> Amount int −> );
使用insert命令在表中插入一些记录。查询如下-
mysql> insert into SumWithIfCondition values('Offline',10); mysql> insert into SumWithIfCondition values('Online',100); mysql> insert into SumWithIfCondition values('Offline',20); mysql> insert into SumWithIfCondition values('Online',200); mysql> insert into SumWithIfCondition values('Offline',30); mysql> insert into SumWithIfCondition values('Online',300);
使用select语句显示表中的所有记录。查询如下-
mysql> select *from SumWithIfCondition;
以下是输出-
+---------------+--------+ | ModeOfPayment | Amount | +---------------+--------+ | Offline | 10 | | Online | 100 | | Offline | 20 | | Online | 200 | | Offline | 30 | | Online | 300 | +---------------+--------+ 6 rows in set (0.00 sec)
这是将一个字符串作为参数的存储过程-
mysql> delimiter // mysql> create procedure sp_GetSumWithPaymentMode11(PaymentMode varchar(200)) −> begin −> select PaymentMode,sum(if(ModeOfPayment=PaymentMode,Amount,0)) as TotalAmount from SumWithIfCondition; −> end // mysql> delimiter ;
现在,您可以使用call命令来调用存储过程。
查询如下-
mysql> call sp_GetSumWithPaymentMode11('Online');
以下是输出-
+-------------+-------------+ | PaymentMode | TotalAmount | +-------------+-------------+ | Online | 600 | +-------------+-------------+ 1 row in set (0.00 sec)
查询如下-
mysql> call sp_GetSumWithPaymentMode11('Offline');
以下是输出-
+-------------+-------------+ | PaymentMode | TotalAmount | +-------------+-------------+ | Offline | 60 | +-------------+-------------+ 1 row in set (0.00 sec)