Question

我想问一下是否可以创建一个if或类似结构的SQL语句。我有两个查询，并希望将它们合并为一个。两者之间的唯一区别是，在WHERE子句中有一个额外的AND条件。我尝试做一个选择案例，但不是很成功。我将创建一个参数“test”，它将占用1或2，并且该条件应该确定要运行的查询。以下是查询...

查询1

SELECT ID,AVG(B.VOL) AS PVOL
FROM (SELECT VAR1 AS ID, SUM(VOL) AS PVOL FROM table1 WHERE VAR1='xyz' 
AND DATE_D>'10/28/2013' AND DATE_D<'10/31/2013'
AND CUSTOMER='Market' AND MARKET='South' AND PROJECT=0
GROUP BY VAR1,DATE_D) B GROUP BY ID

查询2

SELECT ID,AVG(B.VOL) AS PVOL
FROM (SELECT VAR1 AS ID, SUM(VOL) AS PVOL FROM table1 WHERE VAR1='xyz' 
AND DATE_D>'10/28/2013' AND DATE_D<'10/31/2013'
AND PROJECT=0
GROUP BY VAR1,DATE_D) B GROUP BY ID

Answer 1

您可以根据参数@test添加条件，如下所示可以使用相同的查询，根据参数条件的变化。

SELECT ID,AVG(B.VOL) AS PVOL
FROM (SELECT VAR1 AS ID, SUM(VOL) AS PVOL FROM table1 WHERE VAR1='xyz' 
AND DATE_D>'10/28/2013' AND DATE_D<'10/31/2013'
AND ( (@test = 1 AND CUSTOMER='Market' AND MARKET='South' AND PROJECT=0 )
      OR ( @test =2 AND PROJECT=0 )
    )
GROUP BY VAR1,DATE_D) B GROUP BY ID

Answer 2

你可以创建一个接受你希望建立你的IF语句的“test”参数的sproc。

create procedure --sprocname
(
@test int
)
as 
begin
set nocount on
if 
@test = --bool
select statement 1
else 
select statement 2
end

抱歉格式不好我急着设置

条件SQL语句

2 个答案: