Question

我正在尝试使用SQL从数据库导入一些数据到Excel。

我在以下列中获取数据：

项目＃位置数量

但我想以下列格式导入它：

项目＃数量@位置1数量@位置2数量@位置3

选择Distinct item＃，
  情况当location =“location1”那么数量结束时作为QTY @ Location1，
  例如，当location =“location2”那么数量结束为QTY @ Location2，
  情况当location =“location3”那么数量结束时作为QTY @ Location3
  来自table1

然而，这会返回3条记录。有没有办法将这些记录合并为一行？

Answer 1

您想要进行汇总：

Select item#,
       MAX(CASE WHEN location="location1" THEN qty END) AS QTY@Location1,
       MAX(CASE WHEN location="location1" THEN qty END) AS QTY@Location1,
       MAX(CASE WHEN location="location1" THEN qty END) AS QTY@Location1
From table1
Group By item#;

Answer 2

是的，我认为聚合行会起作用

Select item#,
Sum(CASE WHEN location="location1" THEN qty else 0 END) AS QTY@Location1,
Sum(CASE WHEN location="location1" THEN qty else 0 END) AS QTY@Location1,
Sum(CASE WHEN location="location1" THEN qty else 0 END) AS QTY@Location1
From table1
group by
item#

Answer 3

假设'location1''location2'和'location3'是常数，你可以这样做：

SELECT isnull(isnull(loc1.Item, loc2.Item), loc3.Item)  as Item,
       loc1.Qty as QTY@Location1, loc2.Qty as QTY@Location2, loc3.Qty as QTY@Location3
FROM 
  (select Item, Qty from table1 where Location = 'location1') as loc1
FULL JOIN
  (select Item, Qty from table1 where Location = 'location2') as loc2 ON loc1.Item = loc2.Item
FULL JOIN
  (select Item, Qty from table1 where Location = 'location3') as loc3 ON isnull(loc1.Item, loc2.Item) = loc3.Item

Answer 4

如果您的DBMS支持，PIVOT将非常巧妙地为您完成此操作。 [这是]关于这个问题的SO问题。

如何使用SQL将所选数据转换为单行

4 个答案: