Re: SELECT's take a long time compared to other DBMS

От: Hannu Krosing
Тема: Re: SELECT's take a long time compared to other DBMS
Дата: ,
Msg-id: 1062673303.5200.135.camel@fuji.krosing.net
(см: обсуждение, исходный текст)
Ответ на: SELECT's take a long time compared to other DBMS  ("Relaxin")
Список: pgsql-performance

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SELECT's take a long time compared to other DBMS  ("Relaxin", )
 Re: SELECT's take a long time compared to other DBMS  (Rudi Starcevic, )
 Re: SELECT's take a long time compared to other DBMS  (Rod Taylor, )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
  Re: SELECT's take a long time compared to other DBMS  (Rudi Starcevic, )
   Re: SELECT's take a long time compared to other DBMS  (Neil Conway, )
  Re: SELECT's take a long time compared to other DBMS  ("Nick Fankhauser", )
   Re: SELECT's take a long time compared to other DBMS  (Tom Lane, )
   Re: SELECT's take a long time compared to other DBMS  (Jean-Luc Lachance, )
   Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
 Re: SELECT's take a long time compared to other DBMS  (Christopher Browne, )
 Re: SELECT's take a long time compared to other DBMS  (Christopher Browne, )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
  Re: SELECT's take a long time compared to other DBMS  ("Shridhar Daithankar", )
  Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
   Re: SELECT's take a long time compared to other DBMS  ("scott.marlowe", )
 Re: SELECT's take a long time compared to other DBMS  (Hannu Krosing, )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
  Re: SELECT's take a long time compared to other DBMS  (Hannu Krosing, )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
 Re: SELECT's take a long time compared to other DBMS  (William Yu, )
 Re: SELECT's take a long time compared to other DBMS  ("scott.marlowe", )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
 Re: SELECT's take a long time compared to other DBMS  (Christopher Browne, )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
  Re: SELECT's take a long time compared to other DBMS  (Neil Conway, )
  Re: SELECT's take a long time compared to other DBMS  ("Patrick Hatcher", )
  Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
   Re: SELECT's take a long time compared to other DBMS  (Neil Conway, )
  Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
 Re: SELECT's take a long time compared to other DBMS  ("Relaxin", )
  Re: SELECT's take a long time compared to other DBMS  (Eirik Oeverby, )

Relaxin kirjutas N, 04.09.2003 kell 03:28:
> I have a table with 102,384 records in it, each record is 934 bytes.

I created a test database on my Linux (RH9) laptop with 30GB/4200RPM ide
drive and P3-1133Mhz, 768MB, populated it with 128000 rows of 930 bytes
each and did

[hannu@fuji hannu]$ time psql test100k -c 'select * from test' >
/dev/null

real    0m3.970s
user    0m0.980s
sys     0m0.570s

so it seems definitely not a problem with postgres as such, but perhaps
with Cygwin and/or ODBC driver

I also ran the same query  using the "standard" pg adapter:

>>> import pg, time
>>>
>>> con = pg.connect('test100k')
>>>
>>> def getall():
...     t1 = time.time()
...     res = con.query('select * from test')
...     t2 = time.time()
...     list = res.getresult()
...     t3 = time.time()
...     print t2 - t1, t3-t2
...
>>> getall()
3.27637195587 1.10105705261
>>> getall()
3.07413101196 0.996125936508
>>> getall()
3.03377199173 1.07322502136

which gave similar results

------------------------------
Hannu





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