Parallel Degree >> how it works
I want to create an index and I can specify parallel clause and degree. I have seen it works and I have seen PX in v$session.
But my question is, if I create the table with parallel clause and degree and do not specify parallel clause while create index, will oracle create the index in parallel
for example alter table xx parallel 20; and then I do create index .....; (did not specify paralle caluse).
I tried and I can not see PX session in v$session. Thougth to reconfirm that.
If you set object level parallelism then all the queries accessing that object will run in parallel. However, in yor case table scan will happen in parallel but index will not.
by the way, check the parallel sessions in v$px_session (especially DEGREE / REQ_DEGREE columns) & v$px_process views.
Try hard to get what you like OR you will be forced to like what you get.
If you want the index created in parallel you have to specify "parallel" on "create index" statement, I usually create all indexes in parallel, nologging then I add an "alter index" statement setting the index as noparallel, logging.
Pablo (Paul) Berzukov
Author of Understanding Database Administration
available at amazon and other bookstores.
Disclaimer: Advice is provided to the best of my knowledge but no implicit or explicit warranties are provided. Since the advisor explicitly encourages testing any and all suggestions on a test non-production environment advisor should not held liable or responsible for any actions taken based on the given advice.
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