Add additional runs of columnPruningRules and WindowFilterPushDown

Author: xin-zhang2

presto-main-base/src/main/java/com/facebook/presto/sql/planner/PlanOptimizers.java

@@ -733,6 +733,14 @@ public PlanOptimizers(
         builder.add(new SimplifyPlanWithEmptyInput(),
                 new PruneUnreferencedOutputs());
 
+        // Run columnPruningRules one more time to optimize the ProjectNode generated in SimplifyPlanWithEmptyInput.
+        builder.add(new IterativeOptimizer(
+                metadata,
+                ruleStats,
+                statsCalculator,
+                estimatedExchangesCostCalculator,
+                columnPruningRules));
+
         builder.add(new IterativeOptimizer(
                         metadata,
                         ruleStats,
@@ -886,6 +894,7 @@ public PlanOptimizers(
                         // Run RemoveEmptyDelete and EliminateEmptyJoins after table scan is removed by PickTableLayout/AddExchanges
                         ImmutableSet.of(new RemoveEmptyDelete())));
         builder.add(predicatePushDown); // Run predicate push down one more time in case we can leverage new information from layouts' effective predicate
+        builder.add(new WindowFilterPushDown(metadata));
         builder.add(new RemoveUnsupportedDynamicFilters(metadata.getFunctionAndTypeManager()));
         builder.add(simplifyRowExpressionOptimizer); // Should be always run after PredicatePushDown
         builder.add(projectionPushDown);

presto-main-base/src/main/java/com/facebook/presto/sql/planner/optimizations/WindowFilterPushDown.java

@@ -51,7 +51,6 @@
 import static com.facebook.presto.common.type.BigintType.BIGINT;
 import static com.facebook.presto.expressions.LogicalRowExpressions.TRUE_CONSTANT;
 import static com.facebook.presto.sql.planner.plan.ChildReplacer.replaceChildren;
-import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.base.Verify.verify;
 import static com.google.common.collect.Iterables.getOnlyElement;
 import static java.lang.Math.toIntExact;
@@ -116,7 +115,6 @@ public boolean isPlanChanged()
         @Override
         public PlanNode visitWindow(WindowNode node, RewriteContext<Void> context)
         {
-            checkState(node.getWindowFunctions().size() == 1, "WindowFilterPushdown requires that WindowNodes contain exactly one window function");
             PlanNode rewrittenSource = context.rewrite(node.getSource());
 
             if (canReplaceWithRowNumber(node, metadata.getFunctionAndTypeManager())) {