just running a simple select count(1) from a table (using movielens as an example) doesnt seem to work for me. anyone know why this doesnt work? im using hive trunk:
hive> select avg(rating) from movierating where movieid=43; Total MapReduce jobs = 1 Launching Job 1 out of 1 Number of reduce tasks determined at compile time: 1 In order to change the average load for a reducer (in bytes): set hive.exec.reducers.bytes.per.reducer=<number> In order to limit the maximum number of reducers: set hive.exec.reducers.max=<number> In order to set a constant number of reducers: set mapred.reduce.tasks=<number> Starting Job = job_201012141048_0023, Tracking URL = http://localhost:50030/jobdetails.jsp?jobid=job_201012141048_0023 Kill Command = /Users/Sean/dev/hadoop-0.20.2+737/bin/../bin/hadoop job -Dmapred.job.tracker=localhost:8021 -kill job_201012141048_0023 2010-12-20 15:15:03,295 Stage-1 map = 0%, reduce = 0% 2010-12-20 15:15:09,420 Stage-1 map = 50%, reduce = 0% ... eventually fails after a couple of minutes with: 2010-12-20 17:33:01,113 Stage-1 map = 100%, reduce = 0% 2010-12-20 17:33:32,182 Stage-1 map = 100%, reduce = 100% Ended Job = job_201012141048_0023 with errors FAILED: Execution Error, return code 2 from org.apache.hadoop.hive.ql.exec.MapRedTask hive> almost seems like the reduce task never starts. any help would be appreciated. sean