Re: UTF8MatchText

Bruce Momjian wrote:
>
> I do not understand this patch. You have defined two functions,
> UTF8MatchText() and UTF8MatchTextIC(), and the difference between them
> is that one calls CHAREQ and the other calls ICHAREQ, but just above
> those two functions you define the macros identically:
>
> #define CHAREQ(p1, p2) wchareq(p1, p2)
> #define ICHAREQ(p1, p2) wchareq(p1, p2)
>
> Why are there two functions? Also, can't you use one function and just
> pass a boolean to indicate whether case it be ignored?

Sorry, typo:

Why are there two functions? Also, can't you use one function and just
pass a boolean to indicate whether case should be ignored?
------

>
> ---------------------------------------------------------------------------
>
> ITAGAKI Takahiro wrote:
> > "Andrew - Supernews" <andrew(at)supernews(dot)net> wrote:
> >
> > > ITAGAKI> I think all "safe ASCII-supersets" encodings are comparable
> > > ITAGAKI> by bytes, not only UTF-8.
> > >
> > > This is false, particularly for EUC.
> >
> > Umm, I see. I updated the optimization to be used only for UTF8 case.
> > I also added some inlining hints that are useful on my machine (Pentium 4).
> >
> >
> > x1000 of LIKE '%foo% on 10000 rows tables [ms]
> > encoding | HEAD | P1 | P2 | P3
> > -----------+-------+-------+-------+-------
> > SQL_ASCII | 7094 | 7120 | 7063 | 7031
> > LATIN1 | 7083 | 7130 | 7057 | 7031
> > UTF8 | 17974 | 10859 | 10839 | 9682
> > EUC_JP | 17032 | 17557 | 17599 | 15240
> >
> > - P1: UTF8MatchText()
> > - P2: P1 + __inline__ GenericMatchText()
> > - P3: P2 + __inline__ wchareq()
> > (The attached patch is P3.)
> >
> > Regards,
> > ---
> > ITAGAKI Takahiro
> > NTT Open Source Software Center
> >
>
> [ Attachment, skipping... ]
>
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 7: You can help support the PostgreSQL project by donating at
> >
> > http://www.postgresql.org/about/donate
>
> --
> Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
> EnterpriseDB http://www.enterprisedb.com
>
> + If your life is a hard drive, Christ can be your backup. +
>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: don't forget to increase your free space map settings

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +