You're welcome. Filters / comparators shipped with HBase are pretty powerful.
On Thu, Jun 5, 2014 at 3:04 PM, Vrushali C <[email protected]> wrote: > Thanks Ted! Using that regex comparator helped me resolve this. Appreciate > it very much! > > > On Thursday, June 5, 2014 2:23 PM, Ted Yu <[email protected]> wrote: > > > Or, you can use RegexStringComparator. > > Here is a regex string, in Java, that matches columns with prefix c! except > column called c!someName : > > "^c\\!((?!someName).)*$" > > Cheers > > > On Thu, Jun 5, 2014 at 1:26 PM, Ted Yu <[email protected]> wrote: > > > One option is to write your own Comparator (similar to > BinaryPrefixComparator > > in essence) that treats the known column name specially. > > > > Cheers > > > > > > On Thu, Jun 5, 2014 at 12:52 PM, Vrushali C <[email protected]> wrote: > > > >> > >> > >> Hi > >> Is there a way to do this kind of filtering : In my scan, I want to > >> retrieve all columns except for columns starting with a certain prefix. > But > >> within that set of columns being ignored, I have one known column name > that > >> I want to retrieve but ignore the rest. The reason is that columns with > >> this prefix have a lot of data and I am not interested in everything > EXCEPT > >> one of those. > >> > >> So for ignoring the columns with a certain prefix in the scan, I am > doing > >> something like > >> filters.addFilter( > >> new QualifierFilter(CompareFilter.CompareOp.NOT_EQUAL, > >> new BinaryPrefixComparator( > >> Bytes.add(Bytes.toBytes("c!"), Constants.SEP_BYTES)))) > >> > >> Which works. But what I also want to add, is something like this > >> > >> filters.addFilter( > >> new QualifierFilter(CompareFilter.CompareOp.EQUAL, > >> new BinaryPrefixComparator( > >> Bytes.add(Bytes.toBytes("c!someName"), > >> Constants.SEP_BYTES)))) > >> > >> I realize both filters are contradictory to each other, so how do I > >> achieve this? > >> > >> thanks > >> Vrushali > >> > > > > > > >
