[TAJO-729] PreLogicalPlanVerifier verifies distinct aggregation functions incorrectly.

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.8.0, 0.9.0
• Component/s: Planner/Optimizer
• Assignee: Hyunsik Choi
• Reporter: Hyunsik Choi
• Created: 31/Mar/14 13:18
• Updated: 05/Apr/14 17:30
• Resolved: 04/Apr/14 07:47

Description

Since the current Tajo cannot process distinct aggregation functions for multiple columns, PreLogicalPlanVerifier prevents such a case. But, PreLogicalPlanVerifier checks it incorrectly. As a result, it causes a verification error even though a query can be actually executed in Tajo.

See the below example. This query can be actually executed in Tajo.

select
  count(distinct l_orderkey) as v0,
  sum(l_orderkey) as v1,
  sum(l_linenumber) as v2,
  count(*) as v4
from
  lineitem
group by
  l_orderkey;

But, it causes the following verification error.

org.apache.tajo.engine.planner.PlanningException: different DISTINCT columns are not supported yet: l_orderkey, l_linenumber
  at org.apache.tajo.engine.planner.PreLogicalPlanVerifier.visitProjection(PreLogicalPlanVerifier.java:89)
  at org.apache.tajo.engine.planner.PreLogicalPlanVerifier.visitProjection(PreLogicalPlanVerifier.java:33)
  at org.apache.tajo.engine.planner.BaseAlgebraVisitor.visit(BaseAlgebraVisitor.java:55)
  at org.apache.tajo.engine.planner.PreLogicalPlanVerifier.verify(PreLogicalPlanVerifier.java:52)
  at org.apache.tajo.master.GlobalEngine.createLogicalPlan(GlobalEngine.java:247)
  at org.apache.tajo.master.GlobalEngine.executeQuery(GlobalEngine.java:138)
  at org.apache.tajo.master.TajoMasterClientService$TajoMasterClientProtocolServiceHandler.submitQuery(TajoMasterClientService.java:286)
  at org.apache.tajo.ipc.TajoMasterClientProtocol$TajoMasterClientProtocolService$2.callBlockingMethod(TajoMasterClientProtocol.java:513)
  at org.apache.tajo.rpc.BlockingRpcServer$ServerHandler.messageReceived(BlockingRpcServer.java:103)
  at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
  at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
  at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791)
  at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:296)
  at org.jboss.netty.handler.codec.oneone.OneToOneDecoder.handleUpstream(OneToOneDecoder.java:70)
  at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
  at org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791)
  at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:296)
  at org.jboss.netty.handler.codec.frame.FrameDecoder.unfoldAndFireMessageReceived(FrameDecoder.java:462)
  at org.jboss.netty.handler.codec.frame.FrameDecoder.callDecode(FrameDecoder.java:443)
  at org.jboss.netty.handler.codec.frame.FrameDecoder.messageReceived(FrameDecoder.java:303)
  at org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
  at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
  at org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:559)
  at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:268)
  at org.jboss.netty.channel.Channels.fireMessageReceived(Channels.java:255)
  at org.jboss.netty.channel.socket.nio.NioWorker.read(NioWorker.java:88)
  at org.jboss.netty.channel.socket.nio.AbstractNioWorker.process(AbstractNioWorker.java:109)
  at org.jboss.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:312)
  at org.jboss.netty.channel.socket.nio.AbstractNioWorker.run(AbstractNioWorker.java:90)
  at org.jboss.netty.channel.socket.nio.NioWorker.run(NioWorker.java:178)
  at org.jboss.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108)
  at org.jboss.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
  at java.lang.Thread.run(Thread.java:744)