sql(case when 条件)

[liangling221]

$pro_select ="select a.products_id,a.sgg,a.sdw,a.products_price,a.products_erp,
c.products_id,c.products_name,d.idppbh,d.sppmc
from osc_products a,osc_products_description c,brand d
where a.products_id =c.products_id and a.products_id
in (select b.products_id from brand_area_product b where b.idppbh= d.idppbh
and b.idppbh = '" . $brand . "' //如果b.idppbh没有指定为具体的某个值则去掉and b.idppbh = '" . $brand . "' 这个查询条件，如果指定则加上这个条件)
and c.products_name like '%". $pro_name ."%' ";

如果b.idppbh没有指定为具体的某个值则去掉and b.idppbh = '" . $brand . "' 这个查询条件，如果指定则加上这个条件这个 sql语句怎样改？大家多多指教谢谢，，，

$pro_select ="select a.products_id,a.sgg,a.sdw,a.products_price,a.products_erp,
c.products_id,c.products_name,d.idppbh,d.sppmc
from osc_products a,osc_products_description c,brand d
where a.products_id =c.products_id and a.products_id
in (select b.products_id from brand_area_product b where b.idppbh= d.idppbh
case when 。。。。。。then ....
and b.idppbh = '" . $brand . "'
) and c.products_name like '%". $pro_name ."%' ";

[hery2002]

使用 isnull(col,'')这种方式就可以了

[arrow_gx]

//如果b.idppbh没有指定为具体的某个值则去掉and b.idppbh = '" . $brand . "' 这个查询条件，如果指定则加上这个条件 ？？

楼主的意思好像是要组成动态语句， case when 的条件，没有给出来呢，不好分析，提醒一下LZ ,case when 最后面要跟一个end

case when ......then .... end

[hery2002]

类似与这样,自己改改!:)

declare @idppbh nvarchar(10)
set @idppbh ='1234'
select  a.products_id,a.sgg,a.sdw,a.products_price,a.products_erp, 
                      c.products_id,c.products_name,d.idppbh,d.sppmc 
                      from osc_products a,osc_products_description c,brand d  
     where a.products_id =c.products_id and a.products_id 
                in (select b.products_id from brand_area_product b where b.idppbh= d.idppbh  
                 and b.idppbh = isnull(@idppbh '. $brand . ' 
               and c.products_name like '%". $pro_name ."%'

[hery2002]

楼上有点笔误 :(

declare @idppbh nvarchar(10)
set @idppbh ='1234'
select  a.products_id,a.sgg,a.sdw,a.products_price,a.products_erp, 
                      c.products_id,c.products_name,d.idppbh,d.sppmc 
                      from osc_products a,osc_products_description c,brand d  
     where a.products_id =c.products_id and a.products_id 
                in (select b.products_id from brand_area_product b where b.idppbh= d.idppbh  
                 and b.idppbh = isnull(@idppbh,b.idppbh) -- 这样
               and c.products_name like '%". $pro_name ."%'

[-狙击手-]

不明

[Limpire]

$pro_select ="select a.products_id,a.sgg,a.sdw,a.products_price,a.products_erp,
c.products_id,c.products_name,d.idppbh,d.sppmc
from osc_products a,osc_products_description c,brand d
where a.products_id =c.products_id and a.products_id
in (select b.products_id from brand_area_product b where b.idppbh= d.idppbh
and b.idppbh = isnull(nullif('" . $brand . "',''),b.idppbh) //如果b.idppbh没有指定为具体的某个值则去掉and b.idppbh = '" . $brand . "' 这个查询条件，如果指定则加上这个条件)
and c.products_name like '%". $pro_name ."%' ";

[arrow_gx]

这好像和 case when 没什么关系吧

[hzq3554055]

自身相等 。。。。