https://issues.apache.org/jira/browse/CASSANDRA-2406
On Fri, Apr 15, 2011 at 1:43 AM, sam_ <amin_shar...@yahoo.com> wrote: > Hi All, > > I have been using Cassandra 0.7.2 and 0.7.4 with Thrift API (using Java). > > I noticed that if I am querying a Column Family with indexed columns > sometimes I get a duplicate result in get_indexed_slices depending on the > number of rows in the CF and the count that I set in IndexClause.count. > It also depends on the order of rows in CF. > > For example consider the following CF that I call Attributes: > > create column family Attributes with comparator=UTF8Type > and column_metadata=[ > {column_name: range_id, validation_class: LongType, > index_type: KEYS}, > {column_name: attr_key, validation_class: UTF8Type, > index_type: KEYS}, > {column_name: attr_val, validation_class: BytesType, > index_type: KEYS} > ]; > > And suppose I have the following rows in the CF: > > key range_id attr_key attr_val > "1/@1/0", 1, "A", "1" > "1/5/0", 1, "B", "1000" > "3/@1/0", 2, "A", "1" > "3/5/0", 2, "B", "1001" > "5/@1/0", 3, "A", "2" > "5/5/0", 3, "B", "1002" > "7/@1/0", 4, "A", "2" > "7/5/0", 4, "B", "1003" > > Now if I have a query with IndexClause like this (in pseudo code): > > attr_key == "A" AND attr_val == "1" > > with indexClause.count = 4; > > Then I ill get the rows with the following keys from get_indexed_slices : > > "1/@1/0", "3/@1/0", "3/@1/0" > > The last key is a duplicate! > > This is very sensitive to the order of rows in the CF and the number of rows > and the number you set in indexClause.count. I noticed when the number of > rows in the CF is twice the indexClause.count this issue might happen > depending on the order of rows in CF! > > This seems a bug. And it occurs in both 0.7.2 and 0.7.4. > > Is there a solution to this problem? > > Many Thanks, > Sam > > > > > > -- > View this message in context: > http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Duplicate-result-of-get-indexed-slices-depending-on-indexClause-count-tp6275394p6275394.html > Sent from the cassandra-u...@incubator.apache.org mailing list archive at > Nabble.com. > -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of DataStax, the source for professional Cassandra support http://www.datastax.com