> Well, in fact I need to perform "dummy" union with joins; but I cant use
> union, because this
> select is incapsulated into view, and so, first of all it will union
> tables, ant only then will do outer filtering (and, I suppose, without
> indices)
> Maybe I am wrong ?

Dunno exactly - but you should use a join when a join is needed
and you should use a union when a union is needed.

You might want to try UNION ALL instead of plain UNION and
see if that makes a difference.

Martijn Tonies
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> sample :
> TB1 (ID1,DATE1),TB2(ID2,DATE2). ID,DATE1/2 - indexed.
> this would be what I need :
>
> select tb1.id,tb1.date1 from tb1
> where date1 > '2000.01.01'
> union
> select tb2.id2,tb2.date2 from tb2
> where date2 > '2000.01.01'.
>
> date1/2 is indexed field, so results are instant.
>
> But, because of some reason, we have to incapsulate this selection into
> view :
> create view V_A1
> (
> ID,
> DATE0
> )
> AS
> select tb1.id,tb1.date1 from tb1
> union
> select tb2.id2,tb2.date2 from tb2.
>
> And now,
> select * V_A1 where date0 > '2000.01.01'
> is very, very slow....I looks, like FB decides first of all make union
> and then filter it. I definitely know this does not happen with joins :).
> That is why I need make "union" :) via joins :).