Ensure proper rule application order

Before the change, the rule `ImplementOffsetOverOther` could be applied too early, and thus suppress creation of a mandatory SortNode in the resulting plan.
shubhamtagra · May 11, 2019 · 09759d2 · 09759d2
1 parent 488ce45
commit 09759d2
Showing 1 changed file with 8 additions and 2 deletions.
diff --git a/presto-main/src/main/java/io/prestosql/sql/planner/PlanOptimizers.java b/presto-main/src/main/java/io/prestosql/sql/planner/PlanOptimizers.java
@@ -326,8 +326,14 @@ public PlanOptimizers(
                                 new ImplementOffsetOverTopN(),
                                 new ImplementOffsetOverProjectTopN(),
                                 new ImplementOffsetOverSort(),
-                                new ImplementOffsetOverProjectSort(),
-                                new ImplementOffsetOverOther())),
+                                new ImplementOffsetOverProjectSort())),
+                new IterativeOptimizer(
+                        ruleStats,
+                        statsCalculator,
+                        estimatedExchangesCostCalculator,
+                        // Temporary hack: separate optimizer step to avoid a plan that's missing a SortNode over a RowNumber node
+                        // if the rules fires too early
+                        ImmutableSet.of(new ImplementOffsetOverOther())),
                 simplifyOptimizer,
                 new UnaliasSymbolReferences(),
                 new IterativeOptimizer(