Allocate new symbol for field reference

This is to avoid duplicate key exceptions when building the assignments map. Any duplicates expressions are later removed by the optimizers
trinodb · Apr 27, 2013 · 4e140d1 · 4e140d1
1 parent ca9fe50
commit 4e140d1
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Showing 2 changed files with 12 additions and 1 deletion.
diff --git a/presto-main/src/main/java/com/facebook/presto/sql/planner/QueryPlanner.java b/presto-main/src/main/java/com/facebook/presto/sql/planner/QueryPlanner.java
@@ -9,6 +9,7 @@
 import com.facebook.presto.metadata.TableHandle;
 import com.facebook.presto.metadata.TableMetadata;
 import com.facebook.presto.sql.analyzer.Analysis;
+import com.facebook.presto.sql.analyzer.Field;
 import com.facebook.presto.sql.analyzer.FieldOrExpression;
 import com.facebook.presto.sql.analyzer.Session;
 import com.facebook.presto.sql.analyzer.TupleDescriptor;
@@ -154,7 +155,8 @@ private PlanBuilder project(PlanBuilder subPlan, Iterable<FieldOrExpression> exp
             Symbol symbol;
 
             if (fieldOrExpression.isFieldReference()) {
-                symbol = subPlan.translate(fieldOrExpression);
+                Field field = subPlan.getRelationPlan().getDescriptor().getFields().get(fieldOrExpression.getFieldIndex());
+                symbol = symbolAllocator.newSymbol(field);
             }
             else {
                 Expression expression = fieldOrExpression.getExpression();

diff --git a/presto-main/src/test/java/com/facebook/presto/AbstractTestQueries.java b/presto-main/src/test/java/com/facebook/presto/AbstractTestQueries.java
@@ -1065,6 +1065,15 @@ public void testIfExpression()
                 "SELECT sum(CASE WHEN NULLIF(orderstatus, 'F') <> 'F' THEN totalprice ELSE 5.1 END) FROM orders");
     }
 
+    @Test
+    public void testDuplicateFields()
+            throws Exception
+    {
+        assertQuery(
+                "SELECT * FROM (SELECT orderkey, orderkey FROM orders)",
+                "SELECT orderkey, orderkey FROM orders");
+    }
+
     @Test
     public void testCaseInsensitiveOutputAliasInOrderBy()
             throws Exception