[SOLVED] Hbase Scan Filter for Records that are Missing Column or the Column Value is null

Hbase Scan Filter for Records that are Missing Column or the Column Value is null

I have 3 cols {col1, col2, col3} in a col family (CF). I'd like to write a scan such that I select all rows that have col1='val1' and col2='val2' and (col3 is missing or col3 is null).

Doing this in Java - sorry I'm totally new to hbase ;-)

Solution

I had a lot of trouble finding an answer to this myself online. I finally figured it out, and its quite simple - just unanswered:

    Scan scanner = new Scan();

    SingleColumnValueFilter filter = new SingleColumnValueFilter(
        Bytes.toBytes( "some family" ),
        Bytes.toBytes( "some column" ),
        CompareFilter.CompareOp.EQUAL,
        Bytes.toBytes( "" )
    );
    filter.setFilterIfMissing( false );

    scanner.setFilter( filter );
    return scanner;

The key parts of the solution are setting setFilterIfMissing to false and comparing with an empty string.