Re: auditing in postgresql

[Jeff Davis <pgsql(at)j-davis(dot)com>]

On Fri, 2007-08-31 at 16:42 -0400, Merlin Moncure wrote:
> On 8/31/07, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > "Merlin Moncure" <mmoncure(at)gmail(dot)com> writes:
> > > At present, immutable functions are only treated as constants during a
> > > query, which is what we want (no problems with prepare).
> >
> > Uh, no, they'd be folded to constants at plan time, which is exactly
> > what Jeff doesn't want AFAICS.
> 
> yikes! I did test this before I posted that, but I oversimplified it:
> I didn't move the func() to the where clause...do the subselect
> version defined as volatile seems the way to go.  unfortunately this
> means you pay a small extra price for large result sets.
> 

That sounds like a good solution to me. It looks like the planner is
able to optimize the queries, and the audit function is only called
once. It sounds like I may need to beware of future changes, however.

What is the small extra price for large tables though?

Thanks for the help!

Regards,
	Jeff Davis