Question

我正在尝试在 SQL Server 中编写一个执行以下操作的查询：对一个表执行数据聚合查询，然后将结果传递给另一个表。

如果该日期的行已经存在，则更新该列，否则插入新行

INSERT INTO T2 (timevalue, colValue)
    SELECT 
        Time_Stamp_Hour = DATEADD(hh, DATEPART(hh, E3TimeStamp), CAST(CAST(E3TimeStamp AS date) AS datetime)),
        AvgValue = AVG(MyValue)
    FROM
        (SELECT T1.*
         FROM T1
         WHERE (Quality) >= 0) t
    GROUP BY 
       DATEADD(hh, DATEPART(hh, E3TimeStamp), CAST(CAST(E3TimeStamp AS date) AS datetime))
       ON DUPLICATE KEY UPDATE  --TimeStamp matched
            colValue = t.AvgValue

但是，我从这个查询中得到一个语法错误：

<块引用>

关键字“ON”的语法不正确

我不知道怎么回事。有什么想法吗？

非常感谢！

Answer 1

sql server 不支持 upsert 语句，您可以使用 merge :

merge T2 as target
using ( 
select Time_Stamp_Hour=dateadd(hh,datepart(hh,E3TimeStamp), cast(CAST(E3TimeStamp as date) as datetime))
        , AvgValue=AVG(MyValue)
        from (select T1.*
                 from T1
                 where (Quality) >= 0)t
        group by dateadd(hh,datepart(hh,E3TimeStamp), cast(CAST(E3TimeStamp as date) as datetime))
) as source
 on target.timevalue = source.Time_Stamp_Hour 
when not matched 
insert (Time_Stamp_Hour,AvgValue)
when matched 
update set target.colValue= source.AvgValue

使用 Select 语句更新或插入

1 个答案: