10g: parallel pipelined table func - compensating hash() function for parallel_enable clause
Date: Wed, 25 Jan 2012 02:24:58 -0800 (PST)
Message-ID: <c1428c6b-68a2-41aa-aa30-f2a80ba203a5_at_z31g2000vbt.googlegroups.com>
Hi,
How can i compensate the oracle hash function for
parallel_enable(partition myCursor by hash(Some_Key))
Because Some_Key is already a good ID to dispatch to the table
functions.
For a bulk i have e.g. #10 Some_Key values with nearly the same
#number of records per Some_Key value.
This means a balanced load distribution to the parallel pipelined
table function instances.
However oracle requiring hash(Some_Key) undermines the load balancing
(the same for range(Some_Key)).
So i would like to translate Some_Key to a value, that after hash(Some_Key) results in ID (Some_Key) used for dispatch - some kind of anti-hash.
So functionally speaking it ends up in
parallel_enable(partition myCursor by hash(antihash(Some_Key)))
... which effectively is
parallel_enable(partition myCursor by SomeKey)
What's the anti-hash (inverse) function, which compensates for hash(Some_Key)?
- many thanks!
regards,
Frank
Received on Wed Jan 25 2012 - 04:24:58 CST