我使用的是Hive1.1.0、ClouderaCDH5.4.7和Hadoop2.6.0。使用配置单元的聚合函数运行查询时，出现以下错误：
错误：作业提交失败，出现异常“java.lang.illegalargumentexception（无法从空字符串创建路径）”
日志文件：

INFO  : Number of reduce tasks not specified. Defaulting to jobconf value of: 1
INFO  : In order to change the average load for a reducer (in bytes):
INFO  :   set hive.exec.reducers.bytes.per.reducer=<number>
INFO  : In order to limit the maximum number of reducers:
INFO  :   set hive.exec.reducers.max=<number>
INFO  : In order to set a constant number of reducers:
INFO  :   set mapreduce.job.reduces=<number>
WARN  : Hadoop command-line option parsing not performed. Implement the Tool interface and execute your application with ToolRunner to remedy this.
INFO  : Cleaning up the staging area /user/hive/.staging/job_1453471005617_0680
ERROR : Job Submission failed with exception 'java.lang.IllegalArgumentException(Can not create a Path from an empty string)'
java.lang.IllegalArgumentException: Can not create a Path from an empty string
    at org.apache.hadoop.fs.Path.checkPathArg(Path.java:127)
    at org.apache.hadoop.fs.Path.<init>(Path.java:135)
    at org.apache.hadoop.mapreduce.JobSubmitter.copyAndConfigureFiles(JobSubmitter.java:215)
    at org.apache.hadoop.mapreduce.JobSubmitter.copyAndConfigureFiles(JobSubmitter.java:390)
    at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:483)
    at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1306)
    at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1303)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:415)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1671)
    at org.apache.hadoop.mapreduce.Job.submit(Job.java:1303)
    at org.apache.hadoop.mapred.JobClient$1.run(JobClient.java:564)
    at org.apache.hadoop.mapred.JobClient$1.run(JobClient.java:559)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:415)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1671)
    at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:559)
    at org.apache.hadoop.mapred.JobClient.submitJob(JobClient.java:550)
    at org.apache.hadoop.hive.ql.exec.mr.ExecDriver.execute(ExecDriver.java:429)
    at org.apache.hadoop.hive.ql.exec.mr.MapRedTask.execute(MapRedTask.java:137)
    at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:160)
    at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:88)
    at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:1638)
    at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:1398)
    at org.apache.hadoop.hive.ql.Driver.runInternal(Driver.java:1182)
    at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1048)
    at org.apache.hadoop.hive.ql.Driver.run(Driver.java:1043)
    at org.apache.hive.service.cli.operation.SQLOperation.runQuery(SQLOperation.java:144)
    at org.apache.hive.service.cli.operation.SQLOperation.access$100(SQLOperation.java:69)
    at org.apache.hive.service.cli.operation.SQLOperation$1$1.run(SQLOperation.java:196)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:415)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1671)
    at org.apache.hive.service.cli.operation.SQLOperation$1.run(SQLOperation.java:208)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
    at java.util.concurrent.FutureTask.run(FutureTask.java:262)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)

有什么想法吗？