At 17:37 Friday, 07.02.2003 +0000, you wrote:

>In Firebird, is it possible to enforce a uniqueness
>constraint on a combination of more than one column? Or
>even a primary key that spans multiple columns? For
>example: all values of Column A need not be unique, nor
>all values of Column B, but their combination should always
>be unique such that there can be no two rows with the same
>combination of values for both A and B:

Hi,
this is taken from one of my scripts:

ALTER TABLE PC_RASTER_ITEM
ADD CONSTRAINT UNIQUE_PC_RASTER_ITEM UNIQUE (PCRI_START, PCRI_STOP,
PCRI_STEPLENGTH);

HTH,
Markus