选择使用union

Question

我需要在查询中同时使用“union”和“into”。这两个版本运行正常

SELECT x.* INTO 
 NewTABLE FROM
   (SELECT * FROM TABLE1 UNION SELECT * FROM TABLE2) x

或者

SELECT x.* INTO 
 NewTABLE FROM
   (SELECT val1, val2 FROM TABLE1 UNION SELECT val1, val2 FROM TABLE2) x

但我需要的是这样的东西

SELECT x.* INTO 
 NewTABLE FROM
   (SELECT val1, sum(Iif(val2<0,0,val2)) as PositiveVal2 FROM TABLE1 
    UNION SELECT val1, sum(Iif(val2<0,0,val2)) as PositiveVal2 FROM TABLE2) x

看起来总和和/或Iif是问题所在。我该如何解决这个问题！？

Answer 1

你忘记了工会选择的GROUP BY。

SELECT x.* INTO 
 NewTABLE FROM
   (SELECT val1, sum(Iif(val2<0,0,val2)) as PositiveVal2 
    FROM TABLE1 GROUP BY Val1
    UNION 
    SELECT val1, sum(Iif(val2<0,0,val2)) as PositiveVal2 
    FROM TABLE2 GROUP BY Val1) x

您必须聚合或GROUP BY聚合查询中的所有选择字段。