Github user fhueske commented on a diff in the pull request:
https://github.com/apache/flink/pull/5347#discussion_r163878119
--- Diff:
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/nodes/CommonCalc.scala
---
@@ -149,26 +152,42 @@ trait CommonCalc {
// conditions, etc. We only want to account for computations, not for
simple projections.
// CASTs in RexProgram are reduced as far as possible by
ReduceExpressionsRule
// in normalization stage. So we should ignore CASTs here in
optimization stage.
- val compCnt = calcProgram.getExprList.asScala.toList.count {
- case _: RexInputRef => false
- case _: RexLiteral => false
- case c: RexCall if c.getOperator.getName.equals("CAST") => false
- case _ => true
- }
+ // Also, we add 1 to take calc RelNode number into consideration, so
the cost of merged calc
+ // RelNode will less than the total cost of un-merged calcs.
+ val compCnt = calcProgram.getExprList.asScala.toList.count(isCom(_)) +
1
- val newRowCnt = estimateRowCount(calcProgram, rowCnt)
+ val newRowCnt = estimateRowCount(rexBuilder, calcProgram, rowCnt)
planner.getCostFactory.makeCost(newRowCnt, newRowCnt * compCnt, 0)
}
private[flink] def estimateRowCount(
+ rexBuilder: RexBuilder,
--- End diff --
we don't need the `RexBuilder` if we get the condition `RexNode` from the
`RexProgram`.
---
