> On March 20, 2013, 12:42 a.m., Dmitriy Ryaboy wrote:
> > http://svn.apache.org/repos/asf/pig/trunk/src/org/apache/pig/newplan/PColFilterExtractor.java,
> >  line 224
> > <https://reviews.apache.org/r/10035/diff/1/?file=272254#file272254line224>
> >
> >     (A and B) or (C and D)
> >     
> >     is impossible if (A or C) is false. We can push this up, while 
> > retaining the original filter to apply the original filter.
> 
> Rohini Palaniswamy wrote:
>     So just to confirm, you want to extract A and C from each AND condition 
> and push (A OR C) as the partition filter for optimization and still leave 
> ((A AND B) or (C AND D)) to be applied on each tuple?

correct, unless my logic is wrong.

I actually think we made a bad decision when we decided that if we can push 
partitions down, we can drop the filter on the pig side -- this means we can't 
take advantage of partial filters loaders might support (for example, a bloom 
filter a loader can consult to return just the rows that "probably" match the 
condition, as opposed to definitely match. With filter removal, we have to have 
loaders implement a second-pass filtering on top of such filters).


- Dmitriy


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On March 20, 2013, 12:16 a.m., Rohini Palaniswamy wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://reviews.apache.org/r/10035/
> -----------------------------------------------------------
> 
> (Updated March 20, 2013, 12:16 a.m.)
> 
> 
> Review request for pig.
> 
> 
> Description
> -------
> 
> 1) Fixed cases where partition pushdown was not happening for AND and OR 
> construct
> 2) Commented out the negative test cases as they were actually not asserting 
> anything.
> 
> 
> This addresses bug PIG-3173.
>     https://issues.apache.org/jira/browse/PIG-3173
> 
> 
> Diffs
> -----
> 
>   
> http://svn.apache.org/repos/asf/pig/trunk/src/org/apache/pig/newplan/PColFilterExtractor.java
>  1458047 
>   
> http://svn.apache.org/repos/asf/pig/trunk/test/org/apache/pig/test/TestPartitionFilterPushDown.java
>  1458047 
> 
> Diff: https://reviews.apache.org/r/10035/diff/
> 
> 
> Testing
> -------
> 
> Unit tests added and tested few cases manually with hcat.
> 
> 
> Thanks,
> 
> Rohini Palaniswamy
> 
>

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