Question

这是我的问题：

SELECT publicationId AS PublicationID
  FROM dbo.PublicationOwner
 WHERE ownerId = 31331
UNION
SELECT AreaBuy.AreaBuyID AS PublicationID
  FROM AreaBuy 
  JOIN PublicationAreaBuy ON AreaBuy.AreaBuyID = PublicationAreaBuy.AreaBuyID
 WHERE PublicationAreaBuy.PublicationID IN (SELECT publicationId
                                              FROM dbo.PublicationOwner
                                             WHERE ownerId = 31331)
ORDER BY publicationId

我想做的是：

获取所有者ID等于31331的发布ID列表，如果区域购买表中的发布ID在第一个查询的结果中，则添加（联合）任何isabuy id（作为发布ID）。 / p>

有什么问题？是的，31331是正确的所有者ID，并确实返回一个发布ID，该ID也在区域购买表中。

Answer 1

看起来像经典的混音。我没有看到属性publicationId和AreaBuyId之间有任何相似之处。它们可能只是非常糟糕的列:-)。这种不同属性的结合似乎不是正确的方法。

为什么不：

SELECT O.publicationId , A,AreaBuyId
  FROM dbo.PublicationOwner O
  LEFT OUTER JOIN dbo.AreaBuy A
   ON O.AreaBuyId = A.AreaBuyId
 WHERE OwnerId =31331

找到你想要的东西？

Answer 2

我喜欢这种递归CTE的想法，因为我们想要添加到原始列表中。

DECLARE @ownerid INT;
SET @ownerid = 31331;

WITH Publications AS
(
SELECT publicationId AS PublicationID, 'P' AS Rowtype
FROM dbo.PublicationOwner 
WHERE ownerId = @ownerid

UNION ALL

--Note, I am not using the AreaBuy table, because the info is in PublicationAreaBuy
SELECT a.AreaBuyID, 'A' AS Rowtype
FROM Publications AS p
JOIN PublicationAreaBuy AS a
ON a.PublicationID = p.PublicationID
)
SELECT *
FROM Publications
ORDER BY PublicationID
;

并且......执行连接将停止IN子句中的NULL问题。

编辑：下一个查询将在SQL 2005之前的版本中运行

DECLARE @ownerid INT
SET @ownerid = 31331

SELECT publicationId AS PublicationID, 'P' AS Rowtype
FROM dbo.PublicationOwner 
WHERE ownerId = @ownerid

UNION ALL

--Note, I am not using the AreaBuy table, because the info is in PublicationAreaBuy
SELECT a.AreaBuyID, 'A' AS Rowtype
FROM (
      SELECT publicationId AS PublicationID, 'P' AS Rowtype
      FROM dbo.PublicationOwner 
      WHERE ownerId = @ownerid
   ) AS p
JOIN PublicationAreaBuy AS a
ON a.PublicationID = p.PublicationID

ORDER BY PublicationID

SQL联盟问题

2 个答案: