Re: pgsql-server/doc TODO

OK, I removed the TODO item.  It seem too weird.  If others complain
about this, we can document it better.  I personally didn't know IS
TRUE/FALSE even worked.

---------------------------------------------------------------------------

Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > Tom Lane wrote:
> >> momjian@svr1.postgresql.org (Bruce Momjian) writes:
> >>> Add:
> >>> * Allow col IS TRUE/FALSE use an index like col = TRUE/FALSE
> >>
> >> They don't have the same semantics.
>
> > Oh, they don't?  Nulls?
>
> Right.
>
> On second thought it might be possible to optimize this in a similar
> fashion to the IN optimizations, viz only at top level of WHERE, so that
> you can pretend NULL is the same as FALSE.  But it needs some careful
> thought.
>
> A possibly more relevant issue is that indexes on boolean columns are
> seldom of any value anyway, and so optimizing behavior for them seems
> pretty far down the priority list.  In my experience it's more useful to
> create an index on another column(s) with the boolean condition as a
> partial-index predicate.  In this context you can spell the condition
> however you like, it just has to be the same spelling in queries as in
> the index definition...
>
>             regards, tom lane
>

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