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Home -> Community -> Usenet -> c.d.o.tools -> Re: Query Performance
On Thu, 01 Jun 2000 17:29:51 GMT, "Deborah Carter" <dcarter_at_cnfei.com> wrote:
>I am working on this project writing a procedure to select information out
>of some rather large tables and insert them into another table. The
>procedure runs for about 6-8 minutes. How can I improve this performance?
>I believe my select statements are optimized. I just don't know what else
>to check or do to speed up the performance. The query takes so long. I was
>thinking about reorganizing the largest tables as index-organized tables.
>How will this effect performance? What are the drawbacks to index-organized
>tables? Any suggestions are appreciated.
Are you using the Parallel Query Option?
For instance,
insert /*+ APPEND */
into table_x
select /*+ PARALLEL (y,8) */
col1, col2, col3
from table_y
This will fire off 8 processes to query table_y, which can save huge amounts of time. The APPEND directs the insert to append to the table rather than attempt to re-use any existing partially-free blocks, and can help as well.
Chris
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