Re: Materialized views vs. primary keys

On Tue, Apr 05, 2016 at 07:10:56PM -0400, Robert Haas wrote:
> On Tue, Apr 5, 2016 at 6:50 PM, David Fetter <david(at)fetter(dot)org> wrote:
> > Is there a reason other than lack of tuits for this restriction?
>
> "this" lacks an antecedent.

Try to put a primary key on a materialized view, for example:

CREATE TABLE foo(id SERIAL PRIMARY KEY, t text);

CREATE MATERIALIZED VIEW bar AS SELECT * FROM foo;

REFRESH MATERIALIZED VIEW bar;

ALTER MATERIALIZED VIEW bar ADD PRIMARY KEY(id);

At that last step, you get an error that bar is not a table. You get
an identical error with the hoary old trick of

ALTER TABLE bar ADD PRIMARY KEY(id);

This lack prevents things that depend on primary keys (foreign keys,
logical replication, etc.) from operating on the materialized views.

Cheers,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
Skype: davidfetter XMPP: david(dot)fetter(at)gmail(dot)com

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