在虚拟列 INPUT__FILE__NAME 上使用过滤器执行配置单元查询会导致以下异常。
hive> select count(*) from netflow where INPUT__FILE__NAME='vzb.1351794600.0';
FAILED: SemanticException java.lang.RuntimeException: cannot find field input__file__name from [org.apache.hadoop.hive.serde2.objectinspector.UnionStructObjectInspector$MyField@1d264bf5, org.apache.hadoop.hive.serde2.objectinspector.UnionStructObjectInspector$MyField@3d44d0c6,
.
.
.
org.apache.hadoop.hive.serde2.objectinspector.UnionStructObjectInspector$MyField@7e6bc5aa]
此错误与我们在列名错误时得到的错误不同
hive> select count(*) from netflow where INPUT__FILE__NAM='vzb.1351794600.0';
FAILED: SemanticException [Error 10004]: Line 1:35 Invalid table alias or column reference 'INPUT__FILE__NAM': (possible column names are: first, last, ....)
但是在 select 子句中使用这个虚拟列可以正常工作。
hive> select INPUT__FILE__NAME from netflow group by INPUT__FILE__NAME;
Total MapReduce jobs = 1
Launching Job 1 out of 1
Number of reduce tasks not specified. Estimated from input data size: 4
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_201306041359_0006, Tracking URL = http://192.168.0.224:50030/jobdetails.jsp?jobid=job_201306041359_0006
Kill Command = /opt/hadoop/bin/../bin/hadoop job -kill job_201306041359_0006
Hadoop job information for Stage-1: number of mappers: 12; number of reducers: 4
2013-06-14 18:20:10,265 Stage-1 map = 0%, reduce = 0%
2013-06-14 18:20:33,363 Stage-1 map = 8%, reduce = 0%
.
.
.
2013-06-14 18:21:15,554 Stage-1 map = 100%, reduce = 100%
Ended Job = job_201306041359_0006
MapReduce Jobs Launched:
Job 0: Map: 12 Reduce: 4 HDFS Read: 3107826046 HDFS Write: 55 SUCCESS
Total MapReduce CPU Time Spent: 0 msec
OK
hdfs://192.168.0.224:9000/data/jk/vzb/vzb.1351794600.0
Time taken: 78.467 seconds
我正在尝试在已经存在的 HDFS 数据上创建外部配置单元表。我想忽略的文件夹中有额外的文件。类似于以下堆栈流问题中的询问和建议， 如何在 hive 中创建外部表时，如何使 hive 仅将特定文件作为来自 hdfs 文件夹的输入，我可以将位置指向目录中的特定文件吗？
任何帮助，将不胜感激。我得到的完整堆栈跟踪如下
2013-06-14 15:01:32,608 ERROR ql.Driver (SessionState.java:printError(401)) - FAILED: SemanticException java.lang.RuntimeException: cannot find field input__
org.apache.hadoop.hive.ql.parse.SemanticException: java.lang.RuntimeException: cannot find field input__file__name from [org.apache.hadoop.hive.serde2.object
at org.apache.hadoop.hive.ql.optimizer.pcr.PcrOpProcFactory$FilterPCR.process(PcrOpProcFactory.java:122)
at org.apache.hadoop.hive.ql.lib.DefaultRuleDispatcher.dispatch(DefaultRuleDispatcher.java:89)
at org.apache.hadoop.hive.ql.lib.DefaultGraphWalker.dispatch(DefaultGraphWalker.java:87)
at org.apache.hadoop.hive.ql.lib.DefaultGraphWalker.walk(DefaultGraphWalker.java:124)
at org.apache.hadoop.hive.ql.lib.DefaultGraphWalker.startWalking(DefaultGraphWalker.java:101)
at org.apache.hadoop.hive.ql.optimizer.pcr.PartitionConditionRemover.transform(PartitionConditionRemover.java:86)
at org.apache.hadoop.hive.ql.optimizer.Optimizer.optimize(Optimizer.java:102)
at org.apache.hadoop.hive.ql.parse.SemanticAnalyzer.analyzeInternal(SemanticAnalyzer.java:8163)
at org.apache.hadoop.hive.ql.parse.BaseSemanticAnalyzer.analyze(BaseSemanticAnalyzer.java:258)
at org.apache.hadoop.hive.ql.parse.ExplainSemanticAnalyzer.analyzeInternal(ExplainSemanticAnalyzer.java:50)
at org.apache.hadoop.hive.ql.parse.BaseSemanticAnalyzer.analyze(BaseSemanticAnalyzer.java:258)
at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:431)
at org.apache.hadoop.hive.ql.Driver.compile(Driver.java:335)
at org.apache.hadoop.hive.ql.Driver.run(Driver.java:893)
at org.apache.hadoop.hive.cli.CliDriver.processLocalCmd(CliDriver.java:259)
at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:216)
at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:412)
at org.apache.hadoop.hive.cli.CliDriver.run(CliDriver.java:755)
at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:613)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.hadoop.util.RunJar.main(RunJar.java:156)
Caused by: org.apache.hadoop.hive.ql.metadata.HiveException: java.lang.RuntimeException: cannot find field input__file__name from [org.apache.hadoop.hive.ser
at org.apache.hadoop.hive.ql.optimizer.ppr.PartitionPruner.prune(PartitionPruner.java:231)
at org.apache.hadoop.hive.ql.optimizer.pcr.PcrOpProcFactory$FilterPCR.process(PcrOpProcFactory.java:112)
... 23 more
Caused by: java.lang.RuntimeException: cannot find field input__file__name from [org.apache.hadoop.hive.serde2.objectinspector.UnionStructObjectInspector$MyF
at org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorUtils.getStandardStructFieldRef(ObjectInspectorUtils.java:344)
at org.apache.hadoop.hive.serde2.objectinspector.UnionStructObjectInspector.getStructFieldRef(UnionStructObjectInspector.java:100)
at org.apache.hadoop.hive.ql.exec.ExprNodeColumnEvaluator.initialize(ExprNodeColumnEvaluator.java:57)
at org.apache.hadoop.hive.ql.exec.ExprNodeGenericFuncEvaluator.initialize(ExprNodeGenericFuncEvaluator.java:128)
at org.apache.hadoop.hive.ql.optimizer.ppr.PartExprEvalUtils.prepareExpr(PartExprEvalUtils.java:100)
at org.apache.hadoop.hive.ql.optimizer.ppr.PartitionPruner.pruneBySequentialScan(PartitionPruner.java:328)
at org.apache.hadoop.hive.ql.optimizer.ppr.PartitionPruner.prune(PartitionPruner.java:219)
... 24 more