Thanks Adrian and Jerry. Technically, the best way to know which sequence a column is dependent on is to actually query for it. I have functions which query information_schema.columns and run a regex_replace to extract the sequence name from the defaulting nextval() expression. This is better than demanding that sequence names are predictable, but I wonder if there isn't a better query to run that doesn't require parsing texts? Obviously PG knows about the sequence's relation, probably via a dependency that finds it by rendering the text to regclass to an OID... but this stuff makes me nervous. So, a query that returns the sequence name (as text, you can cast to regclass!) associated with a particular column, that would return NUL if there was none... I don't suppose anyone has written such a query before...? Yes, I'd write a function around it! Thanks again, Carlo -----Original Message----- From: Adrian Klaver [mailto:adrian.klaver@xxxxxxxxx] Sent: March 31, 2011 5:29 PM To: Jerry Sievers Cc: Carlo Stonebanks; pgsql-general@xxxxxxxxxxxxxx Subject: Re: Sequence names have 64 character limit? On 03/31/2011 02:13 PM, Jerry Sievers wrote: > Carlo Stonebanks<carlo@xxxxxxxxxxxxx> writes: > >> Whenever I attempt to create a sequence whether this is done directly >> via CREATE SEQUENCE or indrirectly vial declaring a column as SERIAL, >> PG truncates it to 64 characters. Is this a documented limitation? I >> cant find a reference to it. Is it possible to change this >> limitation? > > See the "name" data type. > > As for enlarging it; I'll bet yes but you'll have to compile from source > to do this. > > Someone on the hackers list can better explain :-) See: http://www.postgresql.org/docs/9.0/interactive/sql-syntax-lexical.html 4.1.1. Identifiers and Key Words > >> Our table names are and fully descriptive, and our code depends on a >> predictable sequence naming convention of the PG default >> <table>_<column>_seq. >> >> Yes, I know that its not a great idea to depend on consistent naming >> conventions! >> >> Carlo >> > -- Adrian Klaver adrian.klaver@xxxxxxxxx -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
