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我正在加入多个表，其中我希望根据以下条件将一个列值放入行中TechnicianName：

  • 我有 4 张桌子easy_tbljobcard，easy_tbltechnician并且easy_tblproblemeasy_tbltechnicianMaster

  • 我从存在的 地方进入TechnicianName第二列easy_tbltechnicianMastertechnicianIdeasy_tbltechnician

  • 我想STUFF在我的查询中的第 3 列 ( p.ProblemReported)

当前 SQL 语句：

 SELECT j.CardID, 
      , (SELECT TechnicianName FROM easy_tbltechnicianMaster WHERE TechnicianID = t.technicianID) AS TechnicianName
      , p.ProblemReported 
 FROM easy_tbljobcard AS j 
 JOIN easy_technician AS t ON t.CardID = j.CardID  
 LEFT JOIN easy_tblproblem AS p ON p.CardID = t.CardID

查询结果：

╔══════════╦══════════════════╦═══════════════════╗
║  CardID  ║  TechnicianName  ║  ProblemReported  ║
╠══════════╬══════════════════╬═══════════════════╣
║    1     ║      AKBAR       ║     PROBLEM A     ║
║    1     ║      AKBAR       ║     PROBLEM B     ║
║    1     ║      AKBAR       ║     PROBLEM C     ║
║    1     ║      ASANKA      ║     PROBLEM A     ║
║    1     ║      ASANKA      ║     PROBLEM B     ║
║    1     ║      ASANKA      ║     PROBLEM C     ║
╚══════════╩══════════════════╩═══════════════════╝

上面的结果应该转换成这个：

╔══════════╦══════════════════╦═════════════════════════════════╗
║  CardID  ║  TechnicianName  ║         ProblemReported         ║
╠══════════╬══════════════════╬═════════════════════════════════╣
║    1     ║      AKBAR       ║ PROBLEM A, PROBLEM B, PROBLEM C ║
║    1     ║      ASANKA      ║ PROBLEM A, PROBLEM B, PROBLEM C ║
╚══════════╩══════════════════╩═════════════════════════════════╝

加入多个表时如何做到这一点？

SQLFiddle

4

1 回答 1

12

您可以指定一个CTE – 公用表表达式来存储您的临时结果：

with cteTbl ( CardID
            , TechName
            , problemReported ) as ( 
select j.CardID
     , p.ProblemReported
     , ( select TechnicianName
         from easy_tbltechnicianMaster
         where TechnicianID =  t.technicianID ) as TechName
from easy_tbljobcard as j 
join easy_technician as t on t.CardID = j.CardID  
left join easy_tblproblem as p  on p.CardID = t.CardID )

然后select从中连接所有具有相同的列值t.techName并t.CardID在一行中使用for xml path('')，然后将第一个逗号替换,为stuff：

select t.CardID
     , t.TechName
     , stuff( ( select ', ' + ProblemReported
                from cteTbl
                where TechName = t.TechName
                order by ProblemReported
                for xml path('') ), 1, 1, '') AS ProblemReported
from cteTbl t
group by t.TechName
       , t.CardID

SQLFiddle

于 2014-06-13T16:52:12.273 回答