Re: [SQL] [PERFORM] EXTERNAL storage and substring on long strings

2003-08-14 Thread Joe Conway
Scott Cain wrote:
Oh, and I forgot to mention: it's highly compressed (bzip2 -9) and is
109M.
Thanks. I'll grab a copy from home later today and see if I can find 
some time to poke at it.

Joe



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Re: [SQL] [PERFORM] EXTERNAL storage and substring on long strings

2003-08-08 Thread Scott Cain
Oh, and I forgot to mention: it's highly compressed (bzip2 -9) and is
109M.

Scott

On Tue, 2003-08-05 at 11:01, Scott Cain wrote:
 Joe,
 
 Good idea, since I may not get around to profiling it this week.  I
 created a dump of the data set I was working with.  It is available at
 http://www.gmod.org/string_dump.bz2
 
 Thanks,
 Scott
 
 
 On Mon, 2003-08-04 at 16:29, Joe Conway wrote:
  Is there a sample table schema and dataset available (external-storage 
  case) that we can play with?
  
  Joe
-- 

Scott Cain, Ph. D. [EMAIL PROTECTED]
GMOD Coordinator (http://www.gmod.org/) 216-392-3087
Cold Spring Harbor Laboratory


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Re: [SQL] [PERFORM] EXTERNAL storage and substring on long strings

2003-08-04 Thread Tom Lane
Scott Cain [EMAIL PROTECTED] writes:
 At least this appears to work and is much faster, completing substring
 operations like above in about 0.27 secs (that's about two orders of
 magnitude improvement!)

I find it really, really hard to believe that a crude reimplementation
in plpgsql of the TOAST concept could beat the built-in implementation
at all, let alone beat it by two orders of magnitude.

Either there's something unrealistic about your testing of the
dna_string function, or your original tests are not causing TOAST to be
invoked in the expected way, or there's a bug we need to fix.  I'd
really like to see some profiling of the poor-performing
external-storage case, so we can figure out what's going on.

regards, tom lane

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