At 12:23 PM 1/26/2004, you wrote:
We have a large database that consists of 1 table with 400 fields. I know,
the first thing you are thinking is normalize, it's not an option right now
and the database gets reloaded every 3 months. The table contains marketing
data so it is not as easy to normalize as an employee database, or helpdesk
database for example.

We want to first focus on trying to improve our indexing performance on this
large table. The database (once fully populated) will have 130 million rows.
We performed testing using only 13.5 million and had the following results:

Indexes Time (mins)
Index1  78
Index2  77
Index3  78
Index4  106
Index5  135
Index6  165
Index7  192

You can see that the first 3 indexes seemed to be created in equal amounts
of time but after that, the indexes seemed to add 30mins to each one (almost
to the minute).

I believe cardinality would affect indexing but what are the odds that our
cardinality would create such an accurate graph (graph the points and see).

You can see by the times above that this is unnacceptable. Creating the same
indexes on a MS SQL takes much less time and each index (aside from the
initial cluster index) takes the same amount of time.

Thanks.

Chris.

Chris,
Try creating all indexes with a single Alter Table statement. It should be considerably faster. :)


Mike



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