I can't think of any scenario where leaving Cassandra idle would affect the results returned. I think something else is going on here.
On Fri, Jun 18, 2010 at 2:05 AM, Manfred Muench <docma...@domainerschoice.com> wrote: > Hi, > > I have noticed the following behaviour (bug?) which I don't completely > understand: > 1. start Cassandra (I'm using 0.6.2, but it also appears in 0.6.1) > 2. work with it (I'm using Java thrift API) > 3. let it sit for a long time (in my case: a day or more) without > issuing any command > 4. go back to (2) -- but now Cassandra always returns empty data sets to > queries in Java. The command line interface works, no matter if left > open or started newly. > > Here's how I connect to Cassandra (leaving exception handling out for better > readability): > > --------------------------------------------------------------------- > ... > import org.apache.cassandra.thrift.Cassandra; > import org.apache.thrift.protocol.TBinaryProtocol; > import org.apache.thrift.protocol.TProtocol; > import org.apache.thrift.transport.TSocket; > ... > > TTransport transport = new TSocket(cassandraHost, cassandraPort); > TProtocol protocol = new TBinaryProtocol(transport); > Cassandra.Client client = new Cassandra.Client(protocol); > transport.open(); > ... > List<KeySlice> keySlices = client.get_range_slices(...); > ... > transport.flush(); > transport.close(); > ... > --------------------------------------------------------------------- > > This code usually works, but after leaving Cassandra running unused for a > couple of hours (days), this code connects fine to Cassandra, but the > client.get_range_slices returns an empty result set. > > I am not very sure, but I believe it happens after compacting. Need to do > more tests on this one. > > Does anybody know what I'm doing wrong here? Is there any kind of > "initialisation step" that I should have taken before running queries? > > If you need more (debug) information on this matter, please let me know how > I can provide you with it. The log files didn't show anything while running > the query. The last log message was: > > INFO [COMPACTION-POOL:1] 2010-06-18 14:07:45,882 CompactionManager.java > (line 246) Compacting [] > > I ran the query at around 14:20, no other message after this one. > > Thanks for your help in advance! > > Cheers, > Manfred > > -- > Dr. Manfred Muench > Nanjing Imperiosus Technology Co. Ltd. > Wu Xing Nian Hua Da Sha, Room 1004 > 134 Hanzhong Lu, Nanjing, P.R. China > > > -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
