"Maik" <K.Maik@web.de> wrote in message news:<9na15r$ku4$1@narses.hrz.tu-chemnitz.de>...
> Its clear, union concat the two results.
>
> But he can also use this join version, if its the intention.
>
> select t1.id, sum(t1.amount), t2.id, sum(t2.amount) from table1 as t1,
> table2 as t2 where t1.id=t2.id;
>
> Ciao Maik
This is not right, i wouldnt even bather you if this was the simple
answer.
t1.id=t2.id would mean in doubled or tripled aggregation,
since t1.id and t2.id are not unique, thats why I had to aggregate
them in first Q1, Q2 querires, and link them by ID in the last one.
I don't understand what UNION got to do here. then you probably have
to make three union links of inner, left and right joined tables.
This is not that easy as it seems.
Is there a universal SQL string "expanding" rules, like in math or so?
Thanks