Two questions, need help soon - Mailing list pgsql-general

From John Zhuang
Subject Two questions, need help soon
Date
Msg-id C08F3481F73ED211938100A0C95FC4DF2466@odin.jatotech.com
Whole thread Raw
List pgsql-general
> I have 2 questions about postgres. I recently installed postgreSQL on
> Solaris 2.5.1.
>   1. the pgaccess does not work, when I type "wish -f pgaccess.tcl",
> it gave the following error messages:
>     Error in startup script: couldn't load file "libpgtcl.so":
> ld.so.1: wish: elf error:     /usr/local/pgsql/lib/libpgtcl.so: wrong
> class or data encoding
>         while executing
>     "load libpgtcl.so"
>         (procedure "main" line 3)
>         invoked from within
>     "main $argc $argv"
>         (file "pgaccess.tcl" line 4683)
>   This library: "libpgtcl.so" and "libpq.so" were downloaded from the
> web site of www.flex.ro/pgaccess. They were writen for Redhat Linux,
> so it is not strange that it doesn't work. But how do I make pgaccess
> without the library "libpgtcl.so", is there any other way to do it?
>
>     2. The database's performance is kind of slow when I tried "select
> distinct", perhaps this is only the special case. I had this table
> containing regression test data, right now ~10,000 rows, but only
> contain 4 testdate (Oct 9 - Oct12), testdate is one of the field. So,
> there are many repeated rows of the same testdate, and it takes 3
> minutes to get the results. The query is "select distinct testdate
> from table", and the result is 4 rows of testdates. But if I use the
> query: " select distinct testdate, machine, result, filelist from
> table;", it runs significantly faster, it takes about 12 seconds to
> give 66 rows of results.
>
>     I do not know how "select distinct" is implemented in postgresql,
> to me it seems that it used some algorithm that if the repeated values
> are large, then the speed is much slower. Is there anyway to speed up?
>
> Thanks a lot.
>
> John Zhuang
> Jato Technologies

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