Question

我试图用name1替换所有password1 = 1的显示值，用name2替换password2 = 1而不改变数据库中的实际值。但是当我执行代码时，系统返回：

“pg 4145，第15级，状态1，第22行在预期条件的上下文中指定的非布尔类型的表达式，在“Order”附近。“

我有输出：

name1，name2，GateCode，password1，password2，state
Ryan，Lisa，1,3214,4564，FL
Brandon，Joan，2,5324,1，NV
Leo，Ben，3,1,1，WA

我想要的输出

name1，name2，GateCode，password1，password2，state
Ryan，Lisa，1,3214,4564，FL
Brandon，Joan，2,5324，Joan，NV
Leo，Ben，3，Leo，Ben，WA

这是我的代码：

Select Top 10 
   g.name1 as 'name1'
 , g.name1 as 'name2'
 , c.gateCode as GateCode
 , c.pas1 as 'password1'
 , c.pas2 as 'password2'
 , g.state as 'state'
from guest g
     Left code c
     on g.guest_cdoe = c.guest_code 
Where 
  CASE 
      WHEN password1 = 1 and g.guest_cdoe = c.guest_code
      Then ba.bank_name1
      WHEN password2 = 2 and g.guest_cdoe = c.guest_code
      Then ba.bank_name1
  End
Order by 3

Answer 1

我想这就是你想要的......很难说但是应该指出你正确的方向。您希望select语句中的case不是where语句。

Select Top 10 
   g.name1 as 'name1'
 , g.name2 as 'name2'
 , c.gateCode as GateCode
 , CASE 
      WHEN c.pas1 = 1 and g.guest_cdoe = c.guest_code
      THEN g.name1 
      ELSE c.pas1
   END
 , CASE 
      WHEN c.pas2 = 1 and g.guest_cdoe = c.guest_code
      THEN g.name2 
      ELSE c.pas2
   END
 , g.state as 'state'
from guest g
     Left code c
     on g.guest_cdoe = c.guest_code 
Order by 3

如何正确使用案例陈述？如何使用case语句与where或join表？

1 个答案: