復雜的SQL查詢

Question

有誰知道如何構造以下查詢：

桌子：

TBL_GAME                 id,      name
TBL_CATEGORY             id,      name
LU_GAME_TO_CATEGORY      gameid,  catid
LU_GAME_TO_EVENT         eventid, gameid

因此，基本上Categories有很多游戲。

Events有很多游戲。

我想生成一個報告，以顯示在Events中使用的Games數量列出的Categories 。 按金額降序排列。

這可能嗎 ？

Answer 1

SELECT
       c.id                 as catId,
       c.name               as catName,
       g.id                 as gameId,
       g.name               as gameName,
       sum(ge.INT_QUANTITY) as totalQuantities
FROM
       TBL_CATEGORY         as c,
       TBL_GAME             as g,
       LU_GAME_TO_CATEGORY  as gc,
       LU_GAME_TO_EVENT     as ge
WHERE
       c.id = gc.catId     AND
       g.id = gc.gameId    AND
       g.id = ge.gameId
GROUP BY
       c.id,
       g.id
ORDER BY
       totalQuantities desc,
       c.name,
       g.name

Answer 2

SELECT A.ID, SUM(D.INT_QUANTITY) AS YourSum
FROM TBL_CATEGORY A --Adapt your selected columns 
INNER JOIN LU_GAME_TO_CATEGORY B ON A.id = B.catid
INNER JOIN TBL_CATEGORY C ON B.gameid = C.id
INNER JOIN LU_GAME_TO_EVENT  D ON C.gameid = D.gameid
GROUP BY A.ID
ORDER BY YourSum DESC;

在這里我不調整金額，因為列不存在。 您必須在目標表中添加金額列