Re: Oracle performance - Table with 480 fields

My experience is that "wide tables" perform very poorly when accessed sequentially. On an individual read you may not notice it too much since you are only retrieving one row (assuming you retrieve by key).

This poor performance is especially true if you read a complete table top to bottom, and reference all column names.

Work arounds:
- limit the number of columns you retrieve - use view tables to limit the record set you select (view establishement  even on large tables (500,000 rows, 1 Kb per row) is amazingly quick   compared to trying to read a whole table.

Bart

Melissa Star wrote in message <388CEDD3.7837D7F2_at_inspiration.com.au>...
>Hi everyone,
>
>Do you know if a table with 480 fields will perform well, and whether it
>
>will cause a significant performance difference compared to an ordinary
>table with 20-30 fields?
>
>The table in questions needs to store time-related curve data,
>basically, five minute readings over a 24 hour interval.
>
>If the performance is not going to be acceptable with 480 columns, what
>would be the best solution to store the curve data?
>
>* A one to many relationship or design in which an entire 24 hours is
>not contained in one row may be impossibly slow, since the table will be
>
>accessed VERY frequently
>
>* Using Oracle 8i's array type?
>
>* Storing the full 24 hours of data at a BLOB and manipulating it
>oustide of Oracle only?
>
>Thanks everyone,
>
>Melissa Star
>
Received on Tue Jan 25 2000 - 11:02:59 CST