Perhaps...
SELECT t.c1, sum(t.c2) FROM ( SELECT c11 AS c1, SUM(c12) AS c2 FROM table1 GROUP BY c11 UNION SELECT c21 AS c1,
SUM(c22)AS c2 FROM table2 GROUP BY c21 ) AS t
GROUP BY t.c1
ORDER BY sum(t.c2);
I hope this helps, or at least, give you a clue. Best Regards....
I have not tested it... please
cnliou wrote:
>
> Greetings!
>
> I want to GROUP BY and ORDER BY on the result of UNION similar to the
> following (wrong) SQL:
>
> (SELECT c11 AS c1,SUM(c12) AS c2 FROM table1
> UNION
> SELECT c21 AS c1,SUM(c22) AS c2 FROM table2
> )
> GROUP BY c1
> ORDER BY c2;
>
> Please note that the following is NOT what I want because it generates
> 2 groups of data set:
>
> SELECT c11 AS c1,SUM(c12) AS c2 FROM table1
> GROUP BY c1
> ORDER BY c2
> UNION
> SELECT c21 AS c1,SUM(c22) AS c2 FROM table2
> GROUP BY c1
> ORDER BY c2;
>
> How do I do that? Thank you in advance!
>
> CNLIOU
>
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