Question

这是我上一个问题的后续问题：How to get multiple rows of data into different columns

我的查询与上一个问题中提供的查询非常相似：

SELECT AccountID,
   Value1 = MAX(CASE WHEN RN = 1 THEN Value END),
   Value2 = MAX(CASE WHEN RN = 2 THEN Value END),
   Value3 = MAX(CASE WHEN RN = 3 THEN Value END)
FROM
(
SELECT AccountID,
       Value = CONVERT(VARCHAR(50), Value), -- Cast GUID as VARCHAR(50) to use MAX() in the outer query.
       RN = ROW_NUMBER() OVER (PARTITION BY AccountID ORDER BY Value)
FROM @myTable
) T
GROUP BY AccountID;

我已经将查询输出到一行，如下所示：

AccountID                              Value1                                 Value2                                 Value3
6D68E2C9-4BF8-433B-8BC3-57D87348D034   F0BFA1B1-744A-4DBC-BE27-19D1618D77EA   E22A4B08-40DC-42E5-BC15-72A6912D0D66   A955B30C-5352-4B48-9E96-8A831AFA0751

我现在遇到的问题是我需要使用Value1，Value2和Value3（另一个表中的主键）中的值从其他数据表中获取值。如果我要加入这些值，我最终会再次获得三行。我是否必须做类似的事情或使用支点？

我最终会想要这样的内容：

Account Id                              Value1Table.Color    Value2Table.Color    Value3Table.Color   Value1Table.Size    Value2Table.Size 
6D68E2C9-4BF8-433B-8BC3-57D87348D034    Blue                 Red                  Orange              Large             Small

Answer 1

在转动之前进行查找：

SELECT AccountID, Value1 = MAX(CASE WHEN RN = 1 THEN Value END), Value2 = MAX(CASE WHEN RN = 2 THEN Value END), Value3 = MAX(CASE WHEN RN = 3 THEN Value END) FROM (SELECT AccountID, Value = othertable.color. RN = ROW_NUMBER() OVER (PARTITION BY AccountID ORDER BY Value) FROM @myTable t JOIN othertable ot ON ot.value = t.value ) T GROUP BY AccountID;

如何在SQL中的同一行上加入结果？

1 个答案: