一句sql解决多条件查询的语句怎么写？

[usun82]

表A有pname,tel,email等3个字段，现在是存储过程接收3个对应的参数@pname,@tel,@email
当@pname='0'时，想有这样查询效果 select * from A where tel=@tel and email =@email
当@tel ='0'时，想有这样查询效果 select * from A where pname=@pnameand email =@email
当@email='0'时，想有这样查询效果 select * from A where tel=@tel and pname=@pname
当3个参数都为0时，想有这样查询效果 select * from A
请问用一句话的sql怎么写？谢谢！！！

[usun82]

我的现在是在存储过程中写，不适合拼写字符串。

[dawugui]

在存储过程中用if else去完成.

[htl258_Tony]

select * from A where 
email=case when @email='0' then email else @email end and
pname=case when @pname='0' then pname else @pname end and
tel=case when @tel='0' then tel else @tel end 

[--小F--]

if (@pname='0')
select * from A where tel=@tel and email =@email
else if(@tel ='0') 
....
else if(@email='0')
else if...
...

[dawugui]

begin
if @pname='0' 
   select * from A where tel=@tel and email =@email
else
   begin
   if @tel ='0' 
      select * from A where pname=@pnameand email =@email
   else 
      begin
      if @email='0'
         select * from A where tel=@tel and pname=@pname
      else
         select * from A
      end
   end
end

[htl258_Tony]

select * from A where 
email=case when isnull(@email,'0')='0' then email else @email end and
pname=case when isnull(@pname,'0')='0' then pname else @pname end and
tel=case when isnull(@tel,'0')='0' then tel else @tel end 

最好加个NULL判断

[sxiaohui8709253]

学习 接分

[htl258_Tony]

[Quote=引用 6 楼 htl258 的回复:]
SQL code
select * from A where
email=case when isnull(@email,'0')='0' then email else @email end and
pname=case when isnull(@pname,'0')='0' then pname else @pname end and
tel=case when isnull(@te……
[/Quote]
测试一下,这是我常用的.应该可以达到要求.

[usun82]

谢谢哈！！！

[yujunlin32167]

学习一下....