Re: constraint with check

On 2010-12-13, Viktor Bojović <viktor(dot)bojovic(at)gmail(dot)com> wrote:
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> Hi
> im trying to create foreign key constraint which checks not only the
> existence of key in foreign table, but it has to check if node field has
> value=3Dtrue
> but i don't know how to do that, so im asking for help.

> alter table wg.nc
> add CONSTRAINT "nc_fk" FOREIGN KEY ("Id1")
> REFERENCES "wg"."entities"("Id"),
> check (node=3Dtrue)

you can't do that.

add a node column to wg (and a check node is not distinct fron true constaint and default true) then do this

alter table wg.nc
add CONSTRAINT "nc_fk" FOREIGN KEY ("Id1",node)
REFERENCES "wg"."entities"("Id",node);