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Generate table stats on External tables

Posted on 2013-12-10
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Last Modified: 2013-12-11
Can we generate table statistics on Oracle external table, please suggest.
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Question by:d27m11y
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JJSmith earned 1000 total points
ID: 39710325
Following statement should work on external table SCOTT.EXT_TABLE :

DBMS_STATS.GATHER_TABLE_STATS (
Ownname           => 'SCOTT',
Tabname           => ‘EXT_TABLE’,
estimate_percent  => NULL,
degree      => 4);
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by:d27m11y
ID: 39710356
Looking above, I understand that the syntax looks same as regular tables. May I know what exactly degree above means and why is it set to 4 ?

Thank you !
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by:slightwv (䄆 Netminder)
slightwv (䄆 Netminder) earned 1000 total points
ID: 39710406
To confirm the above generic syntax, the docs seem to imply it can be performed on an external table:
http://docs.oracle.com/cd/E11882_01/server.112/e25494/tables.htm#ADMIN12897

From the docs:
The ANALYZE statement is not supported for gathering statistics for external tables. Use the DBMS_STATS package instead.

>>May I know what exactly degree above means and why is it set to 4 ?
Again the online docs:
docs.oracle.com/cd/E11882_01/appdev.112/e40758/d_stats.htm#ARPLS68583

degree  Degree of parallelism
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by:JJSmith
ID: 39712687
Simply put degree (of Parallelism) - will break down the stats queries into multiple processes which can be run concurrently depending, of course, on the fact that you have multiple CPUs/cores. You get your results quicker!

The import bit in the procedure call that I put up is that the estimate_percent is set to NULL if you have version 10.2; it's OK to use values if you have 9 or 11.
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