Add AggregationNode.hasSingleGlobalAggregation

trinodb · Oct 12, 2022 · a844763 · a844763
1 parent 9134586
commit a844763
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Showing 5 changed files with 13 additions and 7 deletions.
diff --git a/...java/io/trino/sql/planner/iterative/rule/DecorrelateInnerUnnestWithGlobalAggregation.java b/...java/io/trino/sql/planner/iterative/rule/DecorrelateInnerUnnestWithGlobalAggregation.java
@@ -219,8 +219,7 @@ private static boolean isGlobalAggregation(PlanNode node)
         }
 
         AggregationNode aggregationNode = (AggregationNode) node;
-        return aggregationNode.hasEmptyGroupingSet() &&
-                aggregationNode.getGroupingSetCount() == 1 &&
+        return aggregationNode.hasSingleGlobalAggregation() &&
                 aggregationNode.getStep() == SINGLE;
     }
 

diff --git a/.../java/io/trino/sql/planner/iterative/rule/DecorrelateLeftUnnestWithGlobalAggregation.java b/.../java/io/trino/sql/planner/iterative/rule/DecorrelateLeftUnnestWithGlobalAggregation.java
@@ -185,8 +185,7 @@ private static boolean isGlobalAggregation(PlanNode node)
         }
 
         AggregationNode aggregationNode = (AggregationNode) node;
-        return aggregationNode.hasEmptyGroupingSet() &&
-                aggregationNode.getGroupingSetCount() == 1 &&
+        return aggregationNode.hasSingleGlobalAggregation() &&
                 aggregationNode.getStep() == SINGLE;
     }
 

diff --git a/...-main/src/main/java/io/trino/sql/planner/iterative/rule/RemoveEmptyGlobalAggregation.java b/...-main/src/main/java/io/trino/sql/planner/iterative/rule/RemoveEmptyGlobalAggregation.java
@@ -32,8 +32,7 @@ public class RemoveEmptyGlobalAggregation
                     .matching(node ->
                             // no aggregate functions
                             node.getAggregations().isEmpty() &&
-                                    // global aggregation
-                                    node.hasEmptyGroupingSet() && node.getGroupingSetCount() == 1);
+                                    node.hasSingleGlobalAggregation());
 
     @Override
     public Pattern<AggregationNode> getPattern()

diff --git a/core/trino-main/src/main/java/io/trino/sql/planner/optimizations/QueryCardinalityUtil.java b/core/trino-main/src/main/java/io/trino/sql/planner/optimizations/QueryCardinalityUtil.java
@@ -119,7 +119,7 @@ public Range<Long> visitEnforceSingleRow(EnforceSingleRowNode node, Void context
         @Override
         public Range<Long> visitAggregation(AggregationNode node, Void context)
         {
-            if (node.hasEmptyGroupingSet() && node.getGroupingSetCount() == 1) {
+            if (node.hasSingleGlobalAggregation()) {
                 // only single default aggregation which will produce exactly single row
                 return Range.singleton(1L);
             }

diff --git a/core/trino-main/src/main/java/io/trino/sql/planner/plan/AggregationNode.java b/core/trino-main/src/main/java/io/trino/sql/planner/plan/AggregationNode.java
@@ -119,6 +119,15 @@ public GroupingSetDescriptor getGroupingSets()
         return groupingSets;
     }
 
+    /**
+     * @return true if the aggregation collapses all rows into a single global group (e.g., as a result of a GROUP BY () query).
+     * Otherwise, false.
+     */
+    public boolean hasSingleGlobalAggregation()
+    {
+        return hasEmptyGroupingSet() && getGroupingSetCount() == 1;
+    }
+
     /**
      * @return whether this node should produce default output in case of no input pages.
      * For example for query: