RE: Bloom Filter Partition Pruning

From: Jaromir D.B.Nemec <>
Date: Tue, 20 Mar 2018 07:56:32 +0100
Message-ID: <174201d3c018$95e901e0$c1bb05a0$>


one last clarification:  

My test with statistics from V$PX_TQSTAT shows, that while probing a partitioned table in a hash join a BF is used for both partition pruning AND the key filtering.  

This would suggest, that with partitioned tables the described logic of BF based partition pruning is performed *additionally* to the standard way of BF based key filtering.  

Is it a right interpretation?  

Kind Regards,  

Jaromir D.B. Nemec


From: Toon Koppelaars [] Sent: Freitag, 16. März 2018 08:18
Cc: oracle-l-freelists <> Subject: Re: Bloom Filter Partition Pruning  

Normal BF usage hashes the column-values and sets bits based on these hashes in the BF.  

BF partition pruning usage of BF works differently:

Then upon scanning the big table:

On Thu, Mar 15, 2018 at 11:35 PM, Jaromir D.B.Nemec < <> > wrote:

Hi All,

I have basic understanding of the Bloom filter and the mechanism of the  

Received on Tue Mar 20 2018 - 07:56:32 CET

Original text of this message