Question

这可能会造成混淆，但是我敢肯定你们中的一个可以帮助我解决这个问题。所以基本上，我的主表包含以下内容：

ObjID, InfoID, InfoVal, (other columns not needed).

When InfoID = 1, the InfoVal for that row represents the Report name. 
When InfoID = 4, the InfoVal for that row represents the Stored Procedures Name.
When InfoID = 16,17,23 or 24, the InfoVal for that row represents the Email for that Report.

我的问题是，如何将每个条件准确地转换为列并将其全部连接在一起？到目前为止，我有多个单独的查询，其中的InfoID = WHERE条件并且我想将每个专栏连在一起。

基本上，我想要一列用于报告名称，存储过程名称和一列用于电子邮件。

如果您需要可视化的图片，请告诉我！

谢谢。

Answer 1

您似乎想要条件聚合：

select objid,
       max(case when infoid = 1 then infoval end) as report_name,
       max(case when infoid = 4 then infoval end) as stored_procedure_name,
       max(case when infoid = 16 then infoval end) as email1,
       max(case when infoid = 17 then infoval end) as email2,
       max(case when infoid = 23 then infoval end) as email3,
       max(case when infoid = 24 then infoval end) as email4
from t
group by objid;

要过滤：

select t.*
from (select objid,
             max(case when infoid = 1 then infoval end) as report_name,
             max(case when infoid = 4 then infoval end) as stored_procedure_name,
             max(case when infoid = 16 then infoval end) as email1,
             max(case when infoid = 17 then infoval end) as email2,
             max(case when infoid = 23 then infoval end) as email3,
             max(case when infoid = 24 then infoval end) as email4
      from t
      group by objid
    ) t
where email1 like . . .

根据TypeID创建列

1 个答案: