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Viral Bajaria commented on HBASE-9079: -------------------------------------- Looks good to me. I have applied the patch to my local repo and will test with real data in a bit. Will provide an update after that (hopefully before tomorrow). > FilterList getNextKeyHint skips rows that should be included in the results > --------------------------------------------------------------------------- > > Key: HBASE-9079 > URL: https://issues.apache.org/jira/browse/HBASE-9079 > Project: HBase > Issue Type: Bug > Components: Filters > Affects Versions: 0.94.10 > Reporter: Viral Bajaria > Fix For: 0.98.0, 0.95.2, 0.94.11 > > Attachments: 9079-0.94-v2.txt, 9079-trunk-v2.txt, > HBASE-9079-0.94.patch, HBASE-9079-trunk.patch > > > I hit a weird issue/bug and am able to reproduce the error consistently. The > problem arises when FilterList has two filters where each implements the > getNextKeyHint method. > The way the current implementation works is, StoreScanner will call > matcher.getNextKeyHint() whenever it gets a SEEK_NEXT_USING_HINT. This in > turn will call filter.getNextKeyHint() which at this stage is of type > FilterList. The implementation in FilterList iterates through all the filters > and keeps the max KeyValue that it sees. All is fine if you wrap filters in > FilterList in which only one of them implements getNextKeyHint. but if > multiple of them implement then that's where things get weird. > For example: > - create two filters: one is FuzzyRowFilter and second is ColumnRangeFilter. > Both of them implement getNextKeyHint > - wrap them in FilterList with MUST_PASS_ALL > - FuzzyRowFilter will seek to the correct first row and then pass it to > ColumnRangeFilter which will return the SEEK_NEXT_USING_HINT code. > - Now in FilterList when getNextKeyHint is called, it calls the one on > FuzzyRow first which basically says what the next row should be. While in > reality we want the ColumnRangeFilter to give the seek hint. > - The above behavior skips data that should be returned, which I have > verified by using a RowFilter with RegexStringComparator. > I updated the FilterList to maintain state on which filter returns the > SEEK_NEXT_USING_HINT and in getNextKeyHint, I invoke the method on the saved > filter and reset that state. I tested it with my current queries and it works > fine but I need to run the entire test suite to make sure I have not > introduced any regression. In addition to that I need to figure out what > should be the behavior when the opeation is MUST_PASS_ONE, but I doubt it > should be any different. > Is my understanding of it being a bug correct ? Or am I trivializing it and > ignoring something very important ? If it's tough to wrap your head around > the explanation, then I can open a JIRA and upload a patch against 0.94 head. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira