Question

所以这是一笔交易，我能找到的所有Google搜索都具有不同的情况，但与我的情况不符：-）。

这将在VB.net中进行编码，但是由于其sql语法，我以后可以轻松将其构建到vb中。

所以我有一张桌子，我将在桌子上抓一个带数字的行：从TempTable中选择n1，n2，n3，n4，n5

从本质上讲，它将返回类似3、8、12、5、33

我现在有第二个表，它们具有相同的列（n1 ... n5）

我需要找出第二张表中哪些行与第一组数字（3或8或12或5或33）中匹配的数字大于或等于2。

所以如果第二张表看起来像这样：

4、3、57、33、1

5，6，87，21，44

65、3、12、7、8

然后查询应返回2（第一行和最后一行）

我希望这是有道理的：-）

谢谢您的帮助！

Answer 1

我首先将2个表标准化，以便只有一个ID和一个值（如果可能的话，可能还有位置）。我们称它们为A2和B2：

SELECT ID, 1 AS Pos, N1 AS Value FROM A 
UNION ALL
SELECT ID, 2 AS Pos, N2 AS Value FROM A 
UNION ALL
SELECT ID, 3 AS Pos, N3 AS Value FROM A 
UNION ALL
SELECT ID, 4 AS Pos, N4 AS Value FROM A 
UNION ALL
SELECT ID, 5 AS Pos, N5 AS Value FROM A

然后仅获取具有2个或更多匹配项的记录：

SELECT B2.ID, COUNT(*) AS Matches FROM A2 
INNER JOIN B2 ON A2.Value = B2.Value
GROUP BY B2.ID
HAVING COUNT(*) >= 2

最后算一下：

SELECT COUNT(*) FROM ...

在可能看起来像这样的单个查询中（但我建议您为A2和B2创建视图）：

WITH A2 AS (

    -- Normalize table 1
    SELECT ID, 1 AS Pos, N1 AS Value FROM A 
    UNION ALL
    SELECT ID, 2 AS Pos, N2 AS Value FROM A 
    UNION ALL
    SELECT ID, 3 AS Pos, N3 AS Value FROM A 
    UNION ALL
    SELECT ID, 4 AS Pos, N4 AS Value FROM A 
    UNION ALL
    SELECT ID, 5 AS Pos, N5 AS Value FROM A

), B2 AS (

    -- Normalize table 2
    SELECT ID, 1 AS Pos, N1 AS Value FROM B 
    UNION ALL
    SELECT ID, 2 AS Pos, N2 AS Value FROM B 
    UNION ALL
    SELECT ID, 3 AS Pos, N3 AS Value FROM B 
    UNION ALL
    SELECT ID, 4 AS Pos, N4 AS Value FROM B 
    UNION ALL
    SELECT ID, 5 AS Pos, N5 AS Value FROM B

)
-- Count them
SELECT COUNT(*) FROM (
    -- Get only the ones with 2 or more matches
    SELECT B2.ID, COUNT(*) AS Matches FROM A2 
    INNER JOIN B2 ON A2.Value = B2.Value
    GROUP BY B2.ID
    HAVING COUNT(*) >= 2
) AS T

比较数字

1 个答案: