Parallel Query [message #74801] |
Sun, 17 February 2002 23:42 |
Lal
Messages: 2 Registered: February 2002
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Junior Member |
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Hi,
Is it possible to make a query to run in a parellel mode just by setting the int.ora parameters.
PARALLEL_MIN_SERVERS
PARALLEL_MAX_SERVERS
with out giving hints in the sql query?
The scenario is 'We dont have the access to the source code of the product. But we want to make the query to run in a parellel mode' I am using oracle 8.1.7
Any help on this will be appreciated...
Thanks
Lal
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Re: Parallel Query [message #74802 is a reply to message #74801] |
Mon, 18 February 2002 21:05 |
Frank Naude
Messages: 4581 Registered: April 1998
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Senior Member |
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Hi,
Please read the Oracle Parallel Query FAQ at http://www.orafaq.net/faqopq.htm:
Parallel Queries can be performed against tables by doing one of the following:
1. Alter the table (or index) to indicate that Oracle should try to parallelise operations performed against it:
SQL> ALTER TABLE TAB_XXX PARALLEL (DEGREE 7);
2. Put hints in SQL statements to indicate that Oracle should try to execute them in parallel:
SQL> SELECT --+ PARALLEL(table_alias, degree, nodes) * FROM table ...
Best regards.
Frank Naude
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Re: Parallel Query [message #74810 is a reply to message #74801] |
Tue, 16 April 2002 06:59 |
Michael Pritzkow
Messages: 3 Registered: April 2002
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Junior Member |
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To execute a query in parallel it is also nessesary that the data is organised in a parallel fashion, i.e. in a partitioned table and/or index.
With the init.ora parameter parallel_min_percent you can force the optimizer to favor parallel execution over standard rule based execution. But still the optimizer might decide that the query cannot be executed parallelly.
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