Fix regression in field aliasing.

1 files changed, 45 insertions, 42 deletions

diff --git a/exec/java-exec/src/main/java/org/apache/drill/exec/planner/physical/visitor/StarColumnConverter.java b/exec/java-exec/src/main/java/org/apache/drill/exec/planner/physical/visitor/StarColumnConverter.java
index ac7fb8e91..ddc8cf67a 100644
--- a/exec/java-exec/src/main/java/org/apache/drill/exec/planner/physical/visitor/StarColumnConverter.java
+++ b/exec/java-exec/src/main/java/org/apache/drill/exec/planner/physical/visitor/StarColumnConverter.java
@@ -43,39 +43,42 @@ public class StarColumnConverter extends BasePrelVisitor<Prel, boolean[], Runtim
   private static StarColumnConverter INSTANCE = new StarColumnConverter();
 
   private static final AtomicLong tableNumber = new AtomicLong(0);
-    
+
   public static Prel insertRenameProject(Prel root, RelDataType origRowType){
-    // Insert top project to do rename only when : 1) there is a join 
+    // Insert top project to do rename only when : 1) there is a join
     // 2) there is a SCAN with * column.  We pass two boolean to keep track of
-    // these two conditions. 
+    // these two conditions.
     boolean [] renamedForStar = new boolean [2];
     renamedForStar[0] = false;
     renamedForStar[1] = false;
-    
-    //root should be screen / writer : no need to rename for the root.  
+
+    //root should be screen / writer : no need to rename for the root.
 
     Prel child = ((Prel) root.getInput(0)).accept(INSTANCE, renamedForStar);
-    
+
     if (renamedForStar[0] && renamedForStar[1]) {
       List<RexNode> exprs = Lists.newArrayList();
       for (int i = 0; i < origRowType.getFieldCount(); i++) {
         RexNode expr = child.getCluster().getRexBuilder().makeInputRef(origRowType.getFieldList().get(i).getType(), i);
         exprs.add(expr);
       }
-      
+
       RelDataType newRowType = RexUtil.createStructType(child.getCluster().getTypeFactory(), exprs, origRowType.getFieldNames());
- 
-      // Insert a top project which allows duplicate columns. 
+
+      // Insert a top project which allows duplicate columns.
       child = new ProjectAllowDupPrel(child.getCluster(), child.getTraitSet(), child, exprs, newRowType);
 
+      List<RelNode> children = Lists.newArrayList();
+      children.add( child);
+      return (Prel) root.copy(root.getTraitSet(), children);
+
+    }else{
+      return root;
     }
-    
-    List<RelNode> children = Lists.newArrayList();
-    children.add( child);
-    return (Prel) root.copy(root.getTraitSet(), children);
+
   }
 
-  
+
   @Override
   public Prel visitPrel(Prel prel, boolean [] renamedForStar) throws RuntimeException {
     List<RelNode> children = Lists.newArrayList();
@@ -84,14 +87,14 @@ public class StarColumnConverter extends BasePrelVisitor<Prel, boolean[], Runtim
       children.add(child);
     }
 
-    // For project, we need make sure that the project's field name is same as the input, 
+    // For project, we need make sure that the project's field name is same as the input,
     // when the project expression is RexInPutRef. This is necessary since Optiq may use
-    // an arbitrary name for the project's field name. 
+    // an arbitrary name for the project's field name.
     if (prel instanceof ProjectPrel) {
       RelNode child = children.get(0);
-      
+
       List<String> fieldNames = Lists.newArrayList();
-      
+
       for (Pair<String, RexNode> pair : Pair.zip(prel.getRowType().getFieldNames(), ((ProjectPrel) prel).getProjects())) {
         if (pair.right instanceof RexInputRef) {
           String name = child.getRowType().getFieldNames().get(((RexInputRef) pair.right).getIndex());
@@ -100,32 +103,32 @@ public class StarColumnConverter extends BasePrelVisitor<Prel, boolean[], Runtim
           fieldNames.add(pair.left);
         }
       }
-      
-      // Make sure the field names are unique : Optiq does not allow duplicate field names in a rowType. 
+
+      // Make sure the field names are unique : Optiq does not allow duplicate field names in a rowType.
       fieldNames = makeUniqueNames(fieldNames);
-      
+
       RelDataType rowType = RexUtil.createStructType(prel.getCluster().getTypeFactory(), ((ProjectPrel) prel).getProjects(), fieldNames);
 
       return (Prel) new ProjectPrel(prel.getCluster(), prel.getTraitSet(), children.get(0), ((ProjectPrel) prel).getProjects(), rowType);
-    } else {  
+    } else {
       return (Prel) prel.copy(prel.getTraitSet(), children);
     }
   }
 
-  
+
   @Override
   public Prel visitJoin(JoinPrel prel, boolean [] renamedForStar) throws RuntimeException {
-    renamedForStar[0] = true;    // indicate there is a join, which may require top rename projet operator. 
+    renamedForStar[0] = true;    // indicate there is a join, which may require top rename projet operator.
     return visitPrel(prel, renamedForStar);
   }
 
-  
+
   @Override
   public Prel visitScan(ScanPrel scanPrel, boolean [] renamedForStar) throws RuntimeException {
     if (StarColumnHelper.containsStarColumn(scanPrel.getRowType()) && renamedForStar[0] ) {
-      
-      renamedForStar[1] = true;  // indicate there is * for a SCAN operator. 
-      
+
+      renamedForStar[1] = true;  // indicate there is * for a SCAN operator.
+
       List<RexNode> exprs = Lists.newArrayList();
 
       for (RelDataTypeField field : scanPrel.getRowType().getFieldList()) {
@@ -134,34 +137,34 @@ public class StarColumnConverter extends BasePrelVisitor<Prel, boolean[], Runtim
       }
 
       List<String> fieldNames = Lists.newArrayList();
-      
+
       long tableId = tableNumber.getAndIncrement();
-      
+
       for (String name : scanPrel.getRowType().getFieldNames()) {
         fieldNames.add("T" +  tableId + StarColumnHelper.PREFIX_DELIMITER + name);
       }
       RelDataType rowType = RexUtil.createStructType(scanPrel.getCluster().getTypeFactory(), exprs, fieldNames);
 
       ProjectPrel proj = new ProjectPrel(scanPrel.getCluster(), scanPrel.getTraitSet(), scanPrel, exprs, rowType);
-      
+
       return proj;
     } else {
       return visitPrel(scanPrel, renamedForStar);
     }
   }
 
-  
+
   private List<String> makeUniqueNames(List<String> names) {
-    
+
     // We have to search the set of original names, plus the set of unique names that will be used finally .
-    // Eg : the original names : ( C1, C1, C10 ) 
+    // Eg : the original names : ( C1, C1, C10 )
     // There are two C1, we may rename C1 to C10, however, this new name will conflict with the original C10.
     // That means we should pick a different name that does not conflict with the original names, in additional
-    // to make sure it's unique in the set of unique names. 
-    
-    HashSet<String> uniqueNames = new HashSet<String>();    
-    HashSet<String> origNames = new HashSet<String>(names);   
-    
+    // to make sure it's unique in the set of unique names.
+
+    HashSet<String> uniqueNames = new HashSet<String>();
+    HashSet<String> origNames = new HashSet<String>(names);
+
     List<String> newNames = Lists.newArrayList();
 
     for (String s : names) {
@@ -170,13 +173,13 @@ public class StarColumnConverter extends BasePrelVisitor<Prel, boolean[], Runtim
           s = s + i;
           if (! origNames.contains(s) && ! uniqueNames.contains(s))
             break;
-        }        
+        }
       }
       uniqueNames.add(s);
       newNames.add(s);
     }
-    
+
     return newNames;
   }
-  
+
 }