Absolutely
At 01:39 PM 11/18/2003, you wrote:
>Could the column info be used to 'recommend' indexing?
>
>Daniel Fink
>
>Tanel Poder wrote:
>>Hi! If you describe this table then you see that this table stores column
>>usage information in filter and join predicates for database objects.
>> From describe, you see there are several filter and join conditions
>>tracked for an object's (obj#) columns (intcol#). You can join them to
>>col$ table for example. During shutdown, the session executing shutdown,
>>writes the column usage statistics to col_usage$. During normal
>>operations, it's SMON who's doing that over regular intervals. You can
>>disable collecting these statistics by setting _column_tracking_level to
>>0. I don't really see where CBO could use those statistics for speeding
>>up statement execution, because during execution CBO knows all the
>>predicates & statement structure anyway. But it is probably useful for
>>various 10g's advisories, which can make you recommendations based on how
>>the tables (columns) are used. Also, it might help automatic statistics
>>gathering to determine which stats need to be updated or not (this gather
>>stale stuff). Tanel.
>
>Wolfgang Breitling
>Oracle7, 8, 8i, 9i OCP DBA
>Centrex Consulting Corporation
>http://www.centrexcc.com
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Received on Tue Nov 18 2003 - 14:49:26 CST
