How filter Scan of HBase by part of row key?

Question

I have HBase table with row keys, which consist of text ID and timestamp, like next:

...
string_id1.1470913344067
string_id1.1470913345067
string_id2.1470913344067
string_id2.1470913345067
...

How can I filter Scan of HBase (in Scala or Java) to get results with some string ID and timestamp more than some value?

Thanks

Answer 1

Fuzzy row approach is efficient for this kind of requirement and when data is is huge : As explained by this article FuzzyRowFilter takes as parameters row key and a mask info.

In example above, in case we want to find last logged in users and row key format is userId_actionId_timestamp (where userId has fixed length of say 4 chars), the fuzzy row key we are looking for is ????_login_. This translates into the following params for FuzzyRowKey:

FuzzyRowFilter rowFilter = new FuzzyRowFilter(
 Arrays.asList(
  new Pair<byte[], byte[]>(
    Bytes.toBytesBinary("\x00\x00\x00\x00_login_"),
    new byte[] {1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0})));

Would suggest to go through hbase-the-definitive guide -->Client API: Advanced Features