[OPEN-ILS-DEV] Rewrite metabib.rec_descriptor view using crosstab()?

[dkyle at grpl.org]

I don't know how good a test this one query is, but using the same query
as in the expert search bug, I see performance decrease.

http://pastebin.com/wRhKTPWu

Doug.

> Hello all,
>
> I was puzzling today about our planner's apparently inability to properly
> use some of the views (e.g. record_attr, rec_descriptor).  The hstore
> passthru step seems to be the most likely source of opacity, so I wondered
> if we might try to use crosstab() instead.
>
> Here is a (fairly ugly) attempt to do so:
>
> http://pastebin.com/aEvqzXAc
>
> I have very little experience using crosstabs, so this can probably be
> tidied up somehow.  That said, I see promising results on the test data (a
> sample query falls from ~50ms to ~1.5ms), but we need to try it on a
> production set to really see if it helps.
>
> Anyone care to try it out, or weigh in on this approach?  A good test
> might be the "expert search" without Mike's latest patch, or perhaps just
> do some selects of rec_descriptor and see what happens.
>
> Thanks!
> Dan
>
>
> Daniel Wells
> Library Programmer/Analyst
> Hekman Library, Calvin College
> 616.526.7133
>
>
>
>