Re: Foreign key wierdness

Dear Tom, Dave,


Tom Lane wrote:

>Ah-hah, and I'll bet that the column being linked to this one by the
>foreign key constraint is still an integer?
>

It sure is ; being a PostgreSQL novice (BTW : many thanks to the whole 
of the PG development team for such an excellent product), I got on this 
track by means of 
http://archives.postgresql.org/pgsql-sql/2001-05/msg00395.php .


>With two tables each containing some 20.000 entries, the fk creation 
>time between both of them increases from ~ 1.8 secs to ~ 221 secs.
>  
>
>
>Seems odd that the cost would get *that* much worse.  Maybe we need to
>look at whether the FK checking queries need to include explicit casts
>...
>

Well, I reproduced the slowdown with some 20 to 30 different tables.
Anyway, glad I could be of some help, albeit only by testing some 
(probably quite meaningless) border cases ...  :)


Regards,
Didier

-- 

Didier Moens
-----
RUG/VIB - Dept. Molecular Biomedical Research - Core IT
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