[IMPALA-3335] Allow single-node optimization with joins.

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: Impala 2.5.0
• Fix Version/s: Impala 4.0.0
• Component/s: Frontend
• Labels: ramp-up
• Target Version: Product Backlog
• Assignee: Sahil Takiar
• Reporter: Alexander Behm
• Created: 12/Apr/16 23:20
• Updated: 01/Oct/20 19:13
• Resolved: 01/Oct/20 19:13

Description

Now that IMPALA-561 has been fixed, we can remove the workaround that disables the our single-node optimization for any plan with joins. See MaxRowsProcessedVisitor.java:

} else if (caller instanceof HashJoinNode || caller instanceof NestedLoopJoinNode) {
  // Revisit when multiple scan nodes can be executed in a single fragment, IMPALA-561
  abort_ = true;
  return;
}

Issue Links

• depends upon: IMPALA-4866 Hash join node does not apply limits correctly