--- In firebird-support@yahoogroups.com, "Arno Brinkman"
<firebird@a...> wrote:

> I guess field SSTRUKX.IDVISIB has many values which are the same.

yes, you are right

> Remove the index SSTRUK00_IDX3

unbelievable, 4 seconds after removing it

>or create a new compound index on the fields
> (fields from SSTRUK2, IDVISIB).

bad idea, since it was a compound index
details below, i will not create it again

> Regards,
> Arno Brinkman
> ABVisie

the living Optimizer :-)

Thank you very much

Holger

(for anybody who is interested)

here are the indexdefinitions
CREATE INDEX SSTRUK00_IDX1 ON SSTRUK00 (IDVISIB);
CREATE INDEX SSTRUK00_IDX2 ON SSTRUK00 (IDTABELLE);
CREATE INDEX SSTRUK00_IDX3 ON SSTRUK00 (IDVISIB, IDTABELLE);
CREATE INDEX SSTRUK1 ON SSTRUK00 (BEZ);