Use PushProjectionThrough{Union,Exchange} optimizers

prestodb · Apr 10, 2017 · 1f6588a · 1f6588a
1 parent 0443518
commit 1f6588a
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Showing 2 changed files with 13 additions and 3 deletions.
diff --git a/presto-main/src/main/java/com/facebook/presto/sql/planner/PlanOptimizers.java b/presto-main/src/main/java/com/facebook/presto/sql/planner/PlanOptimizers.java
@@ -32,6 +32,8 @@
 import com.facebook.presto.sql.planner.iterative.rule.PushLimitThroughMarkDistinct;
 import com.facebook.presto.sql.planner.iterative.rule.PushLimitThroughProject;
 import com.facebook.presto.sql.planner.iterative.rule.PushLimitThroughSemiJoin;
+import com.facebook.presto.sql.planner.iterative.rule.PushProjectionThroughExchange;
+import com.facebook.presto.sql.planner.iterative.rule.PushProjectionThroughUnion;
 import com.facebook.presto.sql.planner.iterative.rule.RemoveEmptyDelete;
 import com.facebook.presto.sql.planner.iterative.rule.RemoveFullSample;
 import com.facebook.presto.sql.planner.iterative.rule.RemoveRedundantIdentityProjections;
@@ -114,6 +116,13 @@ public PlanOptimizers(Metadata metadata, SqlParser sqlParser, FeaturesConfig fea
         Set<Rule> predicatePushDownRules = ImmutableSet.of(
                 new MergeFilters());
 
+        IterativeOptimizer projectionPushDown = new IterativeOptimizer(
+                stats,
+                ImmutableList.of(new ProjectionPushDown()),
+                ImmutableSet.of(
+                        new PushProjectionThroughUnion(),
+                        new PushProjectionThroughExchange()));
+
         builder.add(
                 new DesugaringOptimizer(metadata, sqlParser), // Clean up all the sugar in expressions, e.g. AtTimeZone, must be run before all the other optimizers
                 new CanonicalizeExpressions(),
@@ -165,7 +174,7 @@ public PlanOptimizers(Metadata metadata, SqlParser sqlParser, FeaturesConfig fea
                 new PredicatePushDown(metadata, sqlParser),
                 new MergeProjections(),
                 new SimplifyExpressions(metadata, sqlParser), // Re-run the SimplifyExpressions to simplify any recomposed expressions from other optimizations
-                new ProjectionPushDown(),
+                projectionPushDown,
                 new UnaliasSymbolReferences(), // Run again because predicate pushdown and projection pushdown might add more projections
                 new PruneUnreferencedOutputs(), // Make sure to run this before index join. Filtered projections may not have all the columns.
                 new IndexJoinOptimizer(metadata), // Run this after projections and filters have been fully simplified and pushed down
@@ -184,7 +193,7 @@ public PlanOptimizers(Metadata metadata, SqlParser sqlParser, FeaturesConfig fea
                 new MetadataQueryOptimizer(metadata),
                 new EliminateCrossJoins(), // This can pull up Filter and Project nodes from between Joins, so we need to push them down again
                 new PredicatePushDown(metadata, sqlParser),
-                new ProjectionPushDown());
+                projectionPushDown);
 
         if (featuresConfig.isOptimizeSingleDistinct()) {
             builder.add(
@@ -211,7 +220,7 @@ public PlanOptimizers(Metadata metadata, SqlParser sqlParser, FeaturesConfig fea
                 ));
 
         builder.add(new PredicatePushDown(metadata, sqlParser)); // Run predicate push down one more time in case we can leverage new information from layouts' effective predicate
-        builder.add(new ProjectionPushDown());
+        builder.add(projectionPushDown);
         builder.add(new MergeProjections());
         builder.add(new UnaliasSymbolReferences()); // Run unalias after merging projections to simplify projections more efficiently
         builder.add(new PruneUnreferencedOutputs());

diff --git a/...-main/src/main/java/com/facebook/presto/sql/planner/optimizations/ProjectionPushDown.java b/...-main/src/main/java/com/facebook/presto/sql/planner/optimizations/ProjectionPushDown.java
@@ -38,6 +38,7 @@
 import static com.facebook.presto.sql.planner.plan.ChildReplacer.replaceChildren;
 import static java.util.Objects.requireNonNull;
 
+@Deprecated
 public class ProjectionPushDown
         implements PlanOptimizer
 {