[PIG-5375] NullPointerException for multi-level self unions with Tez UnionOptimizer

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.18.0
• Hadoop Flags: Reviewed
• Assignee: Koji Noguchi
• Reporter: Koji Noguchi
• Created: 08/Jan/19 22:12
• Updated: 03/Jul/19 17:51
• Resolved: 03/Jul/19 17:51

Description

A = load 'input.txt' as (a0:int, a1: chararray, a2:int);
B = load 'input.txt' as (a0:int, a1: chararray, a2:int);
C = load 'input.txt' as (a0:int, a1: chararray, a2:int);

A_and_B = UNION A, B;
SPLIT A_and_B INTO A_and_B2 IF a0 > 10, A_and_B3 OTHERWISE;

A_and_B_and_C = UNION ONSCHEMA C, A_and_B;

X = UNION ONSCHEMA A_and_B_and_C, A_and_B2, A_and_B3;

X2 = GROUP X ALL ;

dump X2;

This fails on Tez with

Pig Stack Trace
---------------
ERROR 1002: Unable to store alias X2

org.apache.pig.impl.logicalLayer.FrontendException: ERROR 1066: Unable to open iterator for alias X2
        at org.apache.pig.PigServer.openIterator(PigServer.java:1024)
        at org.apache.pig.tools.grunt.GruntParser.processDump(GruntParser.java:790)
        at org.apache.pig.tools.pigscript.parser.PigScriptParser.parse(PigScriptParser.java:383)
        at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:231)
        at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:206)
        at org.apache.pig.tools.grunt.Grunt.exec(Grunt.java:81)
        at org.apache.pig.Main.run(Main.java:630)
        at org.apache.pig.Main.main(Main.java:175)
Caused by: org.apache.pig.PigException: ERROR 1002: Unable to store alias X2
        at org.apache.pig.PigServer.storeEx(PigServer.java:1127)
        at org.apache.pig.PigServer.store(PigServer.java:1086)
        at org.apache.pig.PigServer.openIterator(PigServer.java:999)
        ... 7 more
Caused by: org.apache.pig.backend.executionengine.ExecException: ERROR 0: java.lang.NullPointerException
        at org.apache.pig.backend.hadoop.executionengine.HExecutionEngine.launchPig(HExecutionEngine.java:296)
        at org.apache.pig.PigServer.launchPlan(PigServer.java:1479)
        at org.apache.pig.PigServer.executeCompiledLogicalPlan(PigServer.java:1464)
        at org.apache.pig.PigServer.storeEx(PigServer.java:1123)
        ... 9 more
Caused by: java.lang.NullPointerException
        at org.apache.pig.backend.hadoop.executionengine.tez.plan.TezPOPackageAnnotator.patchPackage(TezPOPackageAnnotator.java:97)
        at org.apache.pig.backend.hadoop.executionengine.tez.plan.TezPOPackageAnnotator.handlePackage(TezPOPackageAnnotator.java:78)
        at org.apache.pig.backend.hadoop.executionengine.tez.plan.TezPOPackageAnnotator.visitTezOp(TezPOPackageAnnotator.java:61)
        at org.apache.pig.backend.hadoop.executionengine.tez.plan.TezOperator.visit(TezOperator.java:265)
        at org.apache.pig.backend.hadoop.executionengine.tez.plan.TezOperator.visit(TezOperator.java:56)
        at org.apache.pig.impl.plan.DepthFirstWalker.depthFirst(DepthFirstWalker.java:69)
        at org.apache.pig.impl.plan.DepthFirstWalker.depthFirst(DepthFirstWalker.java:71)
        at org.apache.pig.impl.plan.DepthFirstWalker.depthFirst(DepthFirstWalker.java:71)
        at org.apache.pig.impl.plan.DepthFirstWalker.walk(DepthFirstWalker.java:52)
        at org.apache.pig.impl.plan.PlanVisitor.visit(PlanVisitor.java:46)
        at org.apache.pig.backend.hadoop.executionengine.tez.TezLauncher.launchPig(TezLauncher.java:197)
        at org.apache.pig.backend.hadoop.executionengine.HExecutionEngine.launchPig(HExecutionEngine.java:290)
        ... 12 more