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HBase, mail # user - Question regarding filtering by column families


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Question regarding filtering by column families
Haijia Zhou 2012-03-06, 18:45
Hi, All

I have this question regarding filtering by column families, basically what
I am doing is to scan a table with a filter on one column family("A") and
process the data of another column family ("B") in the mapper
 my code is as follows:

        FilterList exportFilter = new
FilterList(FilterList.Operator.MUST_PASS_ONE);
        exportFilter.addFilter(new FamilyFilter(CompareOp.EQUAL, new
BinaryComparator("*A*")));

        Scan scan = new Scan();
        scan.addFamily("*B"*);
        scan.setCacheBlocks(false);
        scan.setCaching(10000);
        scan.setFilter(exportFilter);
...

Then somehow the map() method in the mapper class was never executed(The
counter "Map input records" is always 0)

If I comment out the scan.addFamily(..) line, then the map() method would
be executed.

Can someone clarify on this? Should I explicitly add column "A" to the
addFamily()?
Thanks

Haijia
+
T Vinod Gupta 2012-03-06, 18:59
+
Haijia Zhou 2012-03-06, 19:16