Re: performance with many columns

Some additional information:
The data base block size is 8192; the record size is 973; data and indexes are on different tables spaces, on different SCSI controllers.
All configuration parameters in Oracle have been set to the defaults for LARGE (in init.ora) or better.

Most forms of access will always result in a while table scan.

We have been running tests using view tables on the same actual table, with a greatly reduced number of columns (a process called folding) which will substantially increase performance.

What I am looking for is information that can explain why large numbers of columns has such a detrimental impact on performance, and/or suggestions on how to alleviate this.

thanks,

Bart Blom

Bart News wrote in message ...
>I am having serious performance problems with Oracle when using batch
>programs (PRO*C or PRO*COBOL), that need to travers (read from
>top to bottom) fairly wide tables, i.e.
>tables with around 200 columns (table is about 1000 characters wide).
>
>I have plenty memory(1 GB), a fast, 8 CPU, UW7 machine, RAID disk, but
>compared to reading the same file in C-ISAM mode, performance is more than
>7 to 10 times slower. As far as I can tell, my system is configured well.
>
>Using Oracle 8 too, which allows up to 1024 columns.
>
>Any suggestions, pointers to papers ?
>
>Bart Blom
>
>
Received on Fri Jan 07 2000 - 10:37:33 CST