Re: GATHER_SCHEMA_STATS

Morning Deepak,

in a previous contract we had a scheduled task (it was Windows 2000) to gather_schema_stats for a set of 5 different schemas on a 'regular' basis. This was run weekly whether it needed to or not. The app was third party and they specified that this had to be done or support would not be forthcoming.

It was noted that whenever an error occurred in one particular schema, the remainder of that schema was not 'analysed' and no stats were gathered. When I found this out, I rewrote the code to do individual gather_table_stats instead. It took a little longer, but when an exception was raised, I simply had one table with 'bad' stats rather then half a schema.

The exception was raised because there is a bug whereby the stats gathering process barfs if an index on a table has a combined key length of > 4000 (I think) characters. Our third party had built a multi-column index on two VARCHAR2(4000) columns plus a couple of others so that totally screwed the stats gathering.

I don't think they have got around to fixing said index yet, plus, it was never used in queries as far as I could gather :o)

Cheers,
Norman

--

If at first you don't succeed, sky diving probably isn't the sport for you.

Norman Dunbar.
Contract Oracle DBA.
Rivers House, Leeds.

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http://www.freelists.org/webpage/oracle-l Received on Tue Oct 11 2005 - 07:38:30 CDT