MESZAROS Attila wrote:
> I'am faced with a huge system using the above kind of queries.
> It was originally written and tested with adabas.
I wrote a hudge system using those kind of queries. Very
useful buggers, really helps you manage complexity. I bet
it plays hudge games with the optimizer though...
> Unfortunatelly 6.4 does support subqueries only in the 'where' expression,
> as far as I undersood...
That's my understanding. 6.5 will not support it either.
> My questions are:
> How can I port this program with the least effort?
> Shall I create views corresponding to the subqueries,
> and doing the outer select on a view?
You can do this, as long as the inner select does not
have an aggregate. If it has an aggregate _or_ uses an
outer join then you need to code up functions that
do the outer-join.
> Is is planned to implement this feature in the near future?
I hope so. Actually, I think this is a generalization of the HAVING
clause. About 2 years ago (using Oracle) I dropped using the HAVING
clause due to this form... so, there is another possibility,
see if you can re-write these queries to use HAVING.
Let me know if I can help more.
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