Re: rule which unpredictable modify a sequence number - Mailing list pgsql-general

From Tom Lane
Subject Re: rule which unpredictable modify a sequence number
Date
Msg-id 13714.1287851331@sss.pgh.pa.us
Whole thread Raw
In response to rule which unpredictable modify a sequence number  (Armand Turpel <armand.turpel@googlemail.com>)
List pgsql-general
Armand Turpel <armand.turpel@googlemail.com> writes:
> I have a problem with a rule which unpredictable modify a sequence
> number. When I add a new table entry, the new id_keyword hasnt the value
> as expected. ex.: 1000000000000000, 1000000000000001,
> 1000000000000002,...... If i remove the rule it works.

Rules don't play very nicely together with volatile functions like
nextval().  The rule is just a macro, and so if you have multiple
references to new.id_keyword, that means multiple evaluations of
nextval().

You'd be better off using a trigger to do this, I think.

            regards, tom lane

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