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Few questions on PARALLEL option.........
Would be greatful for all your input on each of these questions below.
Can I use PARALLEL option in the CREATE TABLE or ALTER SESSION for an OLTP application OR is this advised only for DSS or DSD applications?
Is is mandatory to use PARALLEL option only if there are more than one CPUs?
Is PARALLEL option same as PARALLEL QUERY (we specify some init.ora parameters to TRUE) option or different? If different, in what way?
Thanks in advance!
PARALLEL OPTION referes to the Parallel Query option in Oracle.
Typically in an OLTP database, there is more overhead associated with setting up the parallel query and tearing it down than you can gain by using parallel queries. If you have a long query, it may benefit from the parallel option.
You can use Parallel Query on 1 CPU machines. You will get best results when your CPU is not the bottleneck on the database.
marist89, thanks for replying.
When you say PARALLEL option is same as PARALLEL QUERY option...... then, do we have to specify it in the CREATE TABLE statement or ONLY in init.ora file or at both places....
Also, could we use PARALLEL option during IMPORT/EXPORT?
If YES, how???
I am assuming that specifying it in init.ora file is MANDATORY.
Correct me if I am wrong.
[Edited by rpardip on 01-05-2001 at 11:58 AM]
You should set some attributes of the table as well as some init.ora parameters. Specify the default degree of parallelism for the table (see http://technet.oracle.com/docs/produ...2a.htm#2056873 )
You can override the default degree of parallelism by using the /*+ PARALLEL */ hint in your DML.
Some DDL statements may be parallelized (see http://technet.oracle.com/docs/produ...paral.htm#5509 )
There is an init.ora paramter that you can initially set that takes care of 80% of the parallel tuning you need ( see http://technet.oracle.com/docs/produ...1135.htm#67101 )
I am not sure about parallel import/export.
[Edited by marist89 on 01-05-2001 at 12:25 PM]
Thanks marist89 for sharing this info.