On Wed, Sep 19, 2012 at 3:05 PM, Daniel Browning <db(at)kavod(dot)com> wrote:
> Another good reason to reject it might be because the only way to disable
> the CTE fence is to disable it by default. If that were the case, then I
> would imagine that it would break backwards compatibility, especially in the
> case of writable CTEs that currently depend on the fence for their current
> functionality.

Yeah: I constantly rely on CTE fencing and it's a frequently suggested
performance trick on the lists.  LATERAL is coming out soon and this
will remove one of the largest reasons to fence but there are of
course others. Also, a GUC setting is almost certainly the wrong
approach.

I'm wondering if there are any technical/standards constraints that
are behind the fencing behavior.  If there aren't any, maybe an opt-in
keyword might do the trick -- WITH UNBOXED foo AS (..)?

merlin

In response to

• CTE optimization fence on the todo list? at 2012-09-19 20:05:44 from Daniel Browning

Responses

• Re: CTE optimization fence on the todo list? at 2012-10-01 13:09:59 from Peter Geoghegan
• Re: CTE optimization fence on the todo list? at 2012-10-01 13:45:54 from Dimitri Fontaine
• Re: CTE optimization fence on the todo list? at 2012-10-01 14:07:01 from Tom Lane

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