Re: Changing ids conflicting with serial values? - Mailing list pgsql-general

From Tom Lane
Subject Re: Changing ids conflicting with serial values?
Date
Msg-id 17183.1130985485@sss.pgh.pa.us
Whole thread Raw
In response to Changing ids conflicting with serial values?  (Steven Brown <swbrown@ucsd.edu>)
Responses Re: Changing ids conflicting with serial values?  (Steven Brown <swbrown@ucsd.edu>)
List pgsql-general
Steven Brown <swbrown@ucsd.edu> writes:
> When I change an id (primary key serial) in a table, the next value
> returned by the sequence for the id can conflict with that id (e.g.,
> change the id to be id + 1).  MySQL seems to handle this transparently
> by skipping conflicting values, but with PostgreSQL I get primary key
> conflicts.  It seems rather bad if a user can modify an id in a row and
> cause failures for all future inserts - it's just too fragile.  What's
> the proper way to handle this in PostgreSQL?

Plan A: don't do that.  Why in the world is it a good idea to modify an
artificial primary key?  It's not like there's some external meaning to
the values.

Plan B: after you do it, adjust the sequence generator with setval().
You can use max() to figure out where to set the generator.

            regards, tom lane

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