Question

我正在尝试创建一个只会在符合某些条件的情况下添加AND子句的查询。

这就是我所追求的：

SELECT DISTINCT
  id
  name
  active
FROM team
WHERE id = 1234
IF team.active = 'y'
  AND team.id IN
    {
       query
    }
ELSEIF team.active = 'n'
  AND team.id IN
    {
      query
    }

但我不确定如何在SQL中执行此操作。有什么建议吗？

Answer 1

 SELECT DISTINCT
    id
    name
    active
    FROM team
 WHERE id = 1234
   AND (team.active = 'y'
     AND team.id IN
        {
          query
        }) 
   OR
    (team.active = 'n'
     AND team.id IN
      {
        query
      })

使用AND和OR连接词来创建逻辑。

Answer 2

你可以像这样使用布尔逻辑

SELECT ...
FROM team
WHERE id = 1234
    AND (
        (team.active = 'y' AND team.id IN query)
        OR
        (team.active = 'n' AND team.id IN query)
    )

我是否错过了两个分支的区别？

Answer 3

您可以使用decode语句来实现结果

SELECT DISTINCT
  id
  name
  active
FROM team
WHERE id = 1234 and
team.id in (
decode (team.active,'y',(query),'n',(query))

您还可以使用案例陈述

SQL - 围绕AND的IF语句

3 个答案: