使用存储过程的 MySQL IF 条件求和查询
mysqlmysqli database更新于 2023/12/7 11:48:00
Sum() 是 MySQL 中的聚合函数。您可以将求和查询与 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 −> ); Query OK, 0 rows affected (1.60 sec)
使用 insert 命令在表中插入一些记录。 查询语句如下 −
mysql> insert into SumWithIfCondition values('Offline',10);
Query OK, 1 row affected (0.21 sec)
mysql> insert into SumWithIfCondition values('Online',100);
Query OK, 1 row affected (0.16 sec)
mysql> insert into SumWithIfCondition values('Offline',20);
Query OK, 1 row affected (0.13 sec)
mysql> insert into SumWithIfCondition values('Online',200);
Query OK, 1 row affected (0.16 sec)
mysql> insert into SumWithIfCondition values('Offline',30);
Query OK, 1 row affected (0.11 sec)
mysql> insert into SumWithIfCondition values('Online',300);
Query OK, 1 row affected (0.17 sec)
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)
以下是接受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 // Query OK, 0 rows affected (0.32 sec) mysql> delimiter ;
现在您可以使用 call 命令调用存储过程.
案例 1 − 适用于在线
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) Query OK, 0 rows affected (0.01 sec)
案例 2 − 适用于离线
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) Query OK, 0 rows affected (0.01 sec)
