[TAJO-739] A subquery with the same column alias caused planning error.

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 0.8.0, 0.9.0
• Assignee: Hyoungjun Kim
• Reporter: Hyoungjun Kim
• Created: 07/Apr/14 01:55
• Updated: 08/Apr/14 07:17
• Resolved: 08/Apr/14 07:07

Description

I ran the bellow query.

select nation.n_nationkey as n_nationkey,
       nation.n_name as n_name
from nation 
inner join (select distinct c_nationkey as n_nationkey from customer) a
on nation.n_nationkey = a.n_nationkey     

2014-04-07 10:52:26,419 ERROR org.apache.tajo.master.querymaster.QueryMasterTask: Already Exists Field: tpch100.a.n_nationkey
org.apache.tajo.catalog.exception.AlreadyExistsFieldException: Already Exists Field: tpch100.a.n_nationkey
        at org.apache.tajo.catalog.Schema.addColumn(Schema.java:287)
        at org.apache.tajo.catalog.Schema.addColumn(Schema.java:299)
        at org.apache.tajo.catalog.Schema.clone(Schema.java:330)
        at org.apache.tajo.engine.utils.SchemaUtil.clone(SchemaUtil.java:66)
        at org.apache.tajo.engine.planner.global.DataChannel.setSchema(DataChannel.java:180)
        at org.apache.tajo.engine.planner.global.DataChannel.<init>(DataChannel.java:55)
        at org.apache.tajo.engine.planner.global.GlobalPlanner.createDataChannelFromJoin(GlobalPlanner.java:157)
        at org.apache.tajo.engine.planner.global.GlobalPlanner.buildJoinPlan(GlobalPlanner.java:258)
        at org.apache.tajo.engine.planner.global.GlobalPlanner.access$300(GlobalPlanner.java:55)
        at org.apache.tajo.engine.planner.global.GlobalPlanner$DistributedPlannerVisitor.visitJoin(GlobalPlanner.java:1006)
        at org.apache.tajo.engine.planner.global.GlobalPlanner$DistributedPlannerVisitor.visitJoin(GlobalPlanner.java:867)
        at org.apache.tajo.engine.planner.BasicLogicalPlanVisitor.visit(BasicLogicalPlanVisitor.java:81)
        at org.apache.tajo.engine.planner.BasicLogicalPlanVisitor.visitRoot(BasicLogicalPlanVisitor.java:133)
        at org.apache.tajo.engine.planner.global.GlobalPlanner$DistributedPlannerVisitor.visitRoot(GlobalPlanner.java:872)
        at org.apache.tajo.engine.planner.global.GlobalPlanner$DistributedPlannerVisitor.visitRoot(GlobalPlanner.java:867)
        at org.apache.tajo.engine.planner.BasicLogicalPlanVisitor.visit(BasicLogicalPlanVisitor.java:58)
        at org.apache.tajo.engine.planner.global.GlobalPlanner.build(GlobalPlanner.java:113)
        at org.apache.tajo.master.querymaster.QueryMasterTask.startQuery(QueryMasterTask.java:346)
        at org.apache.tajo.master.querymaster.QueryMasterTask.start(QueryMasterTask.java:167)
        at org.apache.tajo.master.querymaster.QueryMaster$QueryStartEventHandler.handle(QueryMaster.java:379)
        at org.apache.tajo.master.querymaster.QueryMaster$QueryStartEventHandler.handle(QueryMaster.java:371)
        at org.apache.tajo.master.TajoAsyncDispatcher.dispatch(TajoAsyncDispatcher.java:137)
        at org.apache.tajo.master.TajoAsyncDispatcher$1.run(TajoAsyncDispatcher.java:79)
        at java.lang.Thread.run(Thread.java:744)