Re: Window functions patch v04 for the September commit fest

2008/9/2 Simon Riggs <simon(at)2ndquadrant(dot)com>:
> If you've done all of that, then I'm impressed. Well done.
>
> Few general comments
>
> * The docs talk about "windowing functions", yet you talk about "window
> functions" here. I think the latter is correct, but whichever we choose
> we should be consistent (and hopefully matching SQL Standard).

That's what I'm embarrassed. Now we have "window functions" meaning
two, one for generic name of window expressions and the other for
non-window-aggregates. It is a word play, which is difficult problem
for non-native people, but... let's use "window functions". I'll
revise sgml docs.

> * You don't use duplicate the examples from the docs into the tests,
> which is always a good way to get conflicting reports from users. :-)
>
> * The tests seem very light for such a huge range of new functionality.
> (8 tests is hardly sufficient). I'd like to see a wide range of tests -
> probably 5-10 times as many individual test statements. I would also
> like to see test failures that illustrate the as-yet unimplemented
> features and the warning messages that are thrown - this will help us
> understand exactly what is missing also. It would also be useful to see
> other common coding mistakes/misconceptions and the corresponding error
> messages.
>
>> Also, current implementation has only a type of plan which uses sort
>> operation. It should be optimized by re-position the windows and/or
>> using hashtable.
>
> I would like to see some performance test results also. It would be good
> to know whether they are fast/slow etc.. It will definitely help the
> case for inclusion if they are faster than alternative multi-statement
> approaches to solving the basic data access problems.
>

OK, thanks for your advices. I'll work on tests, docs and benchmarks,
then send in another patch in a week or so.

Regards,

--
Hitoshi Harada