Hi Lorand,
Have you opened JIRA for Hive side?
Thanks
At 2014-10-15 15:53:41, Lorand Bendig lben...@gmail.com wrote:
Hi Rohini and Lulynn,
The exception occurs when DUMP is executed:
X = load 'junit_unparted_basic' using
org.apache.hive.hcatalog.pig.HCatLoader();
dump X
I made some tests on Hive 0.14 / Pig 0.14 and found a bug.
When HCatLoader#setLocation(String location, Job job) is called on the
Hive side, it
can't set the outputschema because
HCatUtil#checkJobContextIfRunningFromBackend(job)
always returns false. This is because in fetch mode we don't have a
mapred.task.id.
A null outputschema will raise an exception when
HCatBaseLoader#getNext() calls
PigHCatUtil#transformToTuple(hr, outputSchema);
I can think of two solutions:
1. At Hive side:
If a job is fetchable then we set
PigImplConstants.CONVERTED_TO_FETCH in the PigContext,
which we could check in
HCatUtil#checkJobContextIfRunningFromBackend(job) .
2. At Pig side:
Set a dummy mapred.task.id when fetch is initialized so that
HCatUtil#checkJobContextIfRunningFromBackend(job) can return true.
I'd go with the first one.
Thanks,
Lorand
On 15/10/14 06:55, Rohini Palaniswamy wrote:
Lorand,
Isn't fetch optimization supposed to be only for DUMP and not STORE ?
-Rohini
On Tue, Oct 14, 2014 at 6:47 PM, lulynn_2008 lulynn_2...@163.com wrote:
Hi Lorand,
The query run fine is I disable fetch. Thanks for your help. Could you
tell why we need to disable fetch?
BTW, I was using pig-0.13.0 and hive-0.13.1.
At 2014-10-14 21:03:13, Lorand Bendig lben...@gmail.com wrote:
Hi,
Which Pig and Hive versions do you use? Does the query run fine if you
disable fetch (set opt.fetch false) ?
Thanks,
Lorand
On 14/10/14 10:50, lulynn_2008 wrote:
Hi All,
I was running HCatStore and HCatLoader in pig grunt. But encounter
ERROR 2088: Fetch failed. Couldn't retrieve result. Please help give a
glance and give your suggestions. Thanks.
Test case:
1. Create table in hive:
create table junit_unparted_basic(a int, b string) stored as RCFILE
tblproperties('hcat.isd'='org.apache.hive.hcatalog.rcfile.RCFileInputDriver','hcat.osd'='org.apache.hive.hcatalog.rcfile.RCFileOutputDriver');
2. copy basic.input.data file into hdfs, here is the content in file:
1S1S
1S2S
1S3S
2S1S
2S2S
2S3S
3S1S
3S2S
3S3S
3. run Pig: pig -useHCatalog
4. grunt A = load 'basic.input.data' as (a:int, b:chararray);
5. grunt store A into 'junit_unparted_basic' using
org.apache.hive.hcatalog.pig.HCatStorer();
6. X = load 'junit_unparted_basic' using
org.apache.hive.hcatalog.pig.HCatLoader();
7. grunt dump X
Error Log:
Pig Stack Trace
---
ERROR 2088: Fetch failed. Couldn't retrieve result
org.apache.pig.impl.logicalLayer.FrontendException: ERROR 1066: Unable
to open iterator for alias X
at org.apache.pig.PigServer.openIterator(PigServer.java:912)
at
org.apache.pig.tools.grunt.GruntParser.processDump(GruntParser.java:752)
at
org.apache.pig.tools.pigscript.parser.PigScriptParser.parse(PigScriptParser.java:372)
at
org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:228)
at
org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:203)
at org.apache.pig.tools.grunt.Grunt.run(Grunt.java:66)
at org.apache.pig.Main.run(Main.java:542)
at org.apache.pig.Main.main(Main.java:156)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:94)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:55)
at java.lang.reflect.Method.invoke(Method.java:619)
at org.apache.hadoop.util.RunJar.main(RunJar.java:212)
Caused by: org.apache.pig.PigException: ERROR 1002: Unable to store
alias X
at org.apache.pig.PigServer.storeEx(PigServer.java:1015)
at org.apache.pig.PigServer.store(PigServer.java:974)
at org.apache.pig.PigServer.openIterator(PigServer.java:887)
... 12 more
Caused by: org.apache.pig.backend.executionengine.ExecException: ERROR
2088: Fetch failed. Couldn't retrieve result
at
org.apache.pig.backend.hadoop.executionengine.fetch.FetchLauncher.runPipeline(FetchLauncher.java:180)
at
org.apache.pig.backend.hadoop.executionengine.fetch.FetchLauncher.launchPig(FetchLauncher.java:81)
at
org.apache.pig.backend.hadoop.executionengine.HExecutionEngine.launchPig(HExecutionEngine.java:275)
at org.apache.pig.PigServer.launchPlan(PigServer.java:1367)
at
org.apache.pig.PigServer.executeCompiledLogicalPlan(PigServer.java:1352)
at org.apache.pig.PigServer.storeEx(PigServer.java:1011)
... 14 more
