Re: Multi-Column Partition keys

First point - you can't do multi-dimensional partitioning with partitioned tables (except in limited cases with composite partitions).

Second point - I don't think it wouldn't help you if you could. Your query allows start time to range over all possibly values, and also allows end time to range over all possible values.

Indexes on start time and end time separately would help for the first two predicates, but the main problem comes from the third
predicate.

--

Jonathan Lewis
Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk

Mike Winterer wrote in message <389F8338.329483B6_at_corp.earthlink.net>...
>We have a situation where there are 2 date columns (starttime and
>endtime) in a table and our most
> common query is of the form
>
> select ..
> from ..
> where (starttime between '10-JAN-2000' and '11-JAN-2000')
> or (endtime between '10-JAN-2000' and '11-JAN-2000')
> or ('10-JAN-2000' between starttime and endtime )
>
> Note that the date range requested can be a day, week, or a month. Also
>note that the date cover
> the range of seconds between midnight and midnight. These are not
>TO_CHAR(:date) values.
>
> The question is "can we partition on both date columns?" If we
>partition on only one or the other
> dates then there will be some records outside of that single column
>range. With the query that we
> are using above we would eliminate some of the search but still have to
>scan the entire index to
> find the range of records of the non-partitioned column.
>
> If we can partition on both of the date columns how will that change
>our queries?
>
>
Received on Tue Feb 08 2000 - 13:23:16 CST