Thread: reference to system table

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.

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.

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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