Re: External function and performance

From: RSH <RSH_Oracle_at_worldnet.att.net>
Date: Mon, 25 Mar 2002 19:14:46 GMT
Message-ID: <GGKn8.5578$se.556686@bgtnsc04-news.ops.worldnet.att.net>

Yes, this is expectable.

Our motto when loading and processing lots of data was to load flat tables, with no derived functions or anything else that would prevent direct, parallel, norecover loads and then pull from the flat tables thus created through a PL/SQL library of after-load processing that we built.

Editing / processing during SQL*LOAD can be murderously expensive unless you have very small input files; otherwise it is best to decouple loading and data scrubbing operations.

RSH. "Krzysztof Ku¶nierz" <kkrzysiek_at_supra.com.pl> wrote in message news:a7iv81$j1t$1_at_news.tpi.pl...
> I have Oracle 9.0.1 working on RedHat Linux 7.2.
> I have noticed that the following statement:
>
> SELECT external_function(column) FROM table
>
> is 10 times slower than:
>
> SELECT column FROM table
>
> where:
> - external_function is empty C function (it only returns its parameter)
> - shared library containig function on the same machine; communication via
> IPC
>
> Is it normal? If not, what can I do to improve performance?
>
> Thanks in advance.
> External function and performance
>
Received on Mon Mar 25 2002 - 13:14:46 CST