模糊 ORA-00904 标识符无效错误

Question

我有一个查询，我在其中构建了一个值表，并将它与另一个查询联合起来。我希望返回一组结果，其中两个表之间的一个值不匹配。 （下面的查询示例）。每次我尝试执行时，都会收到可怕的无效标识符错误，但我不知道为什么。任何建议将不胜感激！

select * from (
select '1234567' as empno, 'A' as status, 'Active' as st_name from dual union all
select '89012345' as empno, 'DA' as status, 'Inactive' as st_name from dual) ft
union 
select id,status,statusnm from second_table st
where st.id = ft.empno
and st.statusnm <> ft.st_name;

有什么想法/建议吗？

Answer 1

你不想要union，你想要join。 . .它应该是明确的：

select st.*
from (select '1234567' as empno, 'A' as status, 'Active' as st_name from dual   
      union all
      select '89012345' as empno, 'DA' as status, 'Inactive' as st_name from dual
     ) ft join
     second_table st 
     on st.id = ft.empno and st.statusnm <> ft.st_name