reference to system table

Started by Antonover 23 years ago3 messagesgeneral
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#1Anton
FreeBSD@list.ru

Hello everybody!

Is there a way to create reference to any system relation?

For example I'd like to create relation which extends pg_shadow with
some attributes such as reference to relation of physical person,
information about worker etcetera.

Thanks in advance
--
Anton

ps My stupid tries:

If I've tried to create reference to pg_shadow(usesysid) pgsql raised
an error.

Then I've tried to inherit pg_shadow but due to inheritance
restriction usesysid and usename become not unique. And if I insert a
tuple into new relation user shouldn't appear in the db.

#2Stephan Szabo
sszabo@megazone23.bigpanda.com
In reply to: Anton (#1)
Re: reference to system table

On Sun, 19 Jan 2003, Anton wrote:

Is there a way to create reference to any system relation?

Not really in general. System tables aren't guaranteed to go
through the same steps for updating as user tables.

#3Bruce Momjian
bruce@momjian.us
In reply to: Stephan Szabo (#2)
Re: reference to system table

Stephan Szabo wrote:

On Sun, 19 Jan 2003, Anton wrote:

Is there a way to create reference to any system relation?

Not really in general. System tables aren't guaranteed to go
through the same steps for updating as user tables.

Right. The best you can do is to create a table that has the extra
column and a userid column, then create a join that shows the join of
pg_shadow and your new table.

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