Question

我有一个看起来简化的SQL Server存储过程：

begin

select
(
case
    when @Method = 'phone' then u.PhoneNumber
    when @Method = 'email' then u.Email
end
)
from
    Table a
join 
    Users u on a.ID = u.Id
where 
    a.Active = 1
    and

    -- This part does not work
    case 
        when @Method = 'phone' then u.PhoneNumber is not null
        when @Method = 'email' then u.Email is not null
    end
end

所以问题是我不想要空值，电话和电子邮件都可以为空。因此，如果@Method参数是phone，我不希望u.PhoneNumber中的空值，当输入参数是电子邮件时，我不希望u.Email列中包含空值。

解决这个问题的最佳方法是什么？

Answer 1

您无需在可以使用的地方使用案例

where 
a.Active = 1
and

-- This part now work
(
    (@Method = 'phone' and u.PhoneNumber is not null) OR
    (@Method = 'email' and u.Email is not null)
)

Answer 2

更改您的位置条件如下

where 
a.Active = 1
and (
     (@Method = 'phone' and u.PhoneNumber is not null)
     or 
     (@Method = 'email' and u.Email is not null)
   )

Answer 3

它就像你的选择陈述

where 
a.Active = 1
and
case 
    when @Method = 'phone' then u.PhoneNumber 
    when @Method = 'email' then u.Email 
end is not null

我在where子句时的SQL Server Procedure Case

3 个答案: