Re: bk commit into 5.0 tree (gshchepa:1.2527) BUG#29338

[Konstantin Osipov]

* gshchepa@stripped <gshchepa@stripped> [07/07/19 17:27]:
> ChangeSet@stripped, 2007-07-19 18:39:01+05:00, gshchepa@stripped +4 -0
>   Fixed bug #29338.
>   Optimization of queries with DETERMINISTIC functions in the
>   WHERE clause was not effective: sequential scan was always
>   used.
>   Now a SF with the DETERMINISTIC flags is treated as constant
>   when it's arguments are constants (or a SF doesn't has arguments).

I think it is a reasonable compromise and agree with Serg's
review.

It would be nice, still, to clarify the point of view of the SQL
standard in the changeset comment, or, better, in the comment in
the source code.

How does the current behaviour correlate with the standard?

Does the standard specify how many times and when a
non-deterministic function is invoked in a query?

What optimizations does the standard allow for deterministic
functions?

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-- Konstantin Osipov              Software Developer, Moscow, Russia
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