Re: update on TOAST status'

> Bruce Momjian wrote:
> > > - VACUUM doesn't propagate ANALYZE to TOAST tables.
> > > Statistics for them are needless because the toast access
> > > is allways hardcoded indexed.
> >
> > I don't think statistics are insignificant for TOASTed columns. If I
> > say col=3, the optimizer uses that information for estimating the number
> > of rows returned, and figuring out the type of join and order of join to
> > perform, not just for "use index, don't use index" decisions.
>
> Ask your boys to give you a training session for "reading"
> when they go to bed tonight - and greet them from the "police
> officer" :-)

Sure.

>
> I said "to TOAST tables", not "TOASTed columns".
>
> Their master tables will allways have the statistics,
> including those for toasted columns, if you ask for them via
> ANALYZE.
>
> In normal operation, noone would ever know if a TOAST table
> is accessed during his query - not even the planner or
> optimmizer. It's totally transparent and the only one
> accessing the TOAST tables is the toaster himself - and he
> knows what he does.
>

Oh, sure, got it. It is the toast table that doesn't need stats.

--
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