Re: performance problem

From: <andreas.prusch_at_sintec.de>
Date: Tue, 26 May 1998 06:11:35 GMT
Message-ID: <6kdmem$j9c$1@nnrp1.dejanews.com>

I can't exactly see the problem. But if number in the select statement is the varchar2 column then the statement is change to select * from MaschDat where to_number(number) = 100 by Oracle with the result of a full table scan. If you write the statement select * from MaschDat where number = '100' then Oracle uses the index. Nearby, don't use keywords like number in select statements or table definitions for column names. And when, then use "number".

I hope this will help.
Andreas Prusch

In article <35696D47.AA701111_at_delphinsys.de>, "Klaus Hümmeler" <khuemmeler_at_delphinsys.de> wrote:
>
> Hi,
>
> I'm testing the performance of an Oracle8 evaluating version. Therefor I
> created a table with nearly 20000 rows containing 180 MB of data (number
> and varchar2).
> I made an primary index of one Column (varchar2) wich contains the
> entry-number.
>
> Every question like e.g. "select * from MaschDat where number = 100"
> takes
> nearly 2 Minutes until I get the selected row(s).
>
> Is Oracle really so slow, or what is my mistake??? The System, where
> Oracle is running, is an NT-Server with 200 MHz Pentium an 64 MB Ram.
>
> Please give me a hint for solving this problem!
>
> Regards Klaus
>
> ---
> Dipl.-Ing. Klaus Huemmeler
> Delphin Prozesstechnik
> 51515 Kürten / Germany
> EMail: khuemmeler_at_delphinsys.de
>
>

-----== Posted via Deja News, The Leader in Internet Discussion ==----- http://www.dejanews.com/ Now offering spam-free web-based newsreading Received on Tue May 26 1998 - 01:11:35 CDT