diff --git a/lib/Doctrine/ORM/Query/Parser.php b/lib/Doctrine/ORM/Query/Parser.php
index a3725eb8d..ff3656b62 100644
--- a/lib/Doctrine/ORM/Query/Parser.php
+++ b/lib/Doctrine/ORM/Query/Parser.php
@@ -2,7 +2,7 @@
 /*
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHARNTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
@@ -1305,7 +1305,7 @@ class Parser
     }
 
     /**
-     * GroupByItem ::= IdentificationVariable | SingleValuedPathExpression
+     * GroupByItem ::= IdentificationVariable | ResultVariable | SingleValuedPathExpression
      *
      * @return string | \Doctrine\ORM\Query\AST\PathExpression
      */
@@ -1314,18 +1314,20 @@ class Parser
         // We need to check if we are in a IdentificationVariable or SingleValuedPathExpression
         $glimpse = $this->_lexer->glimpse();
 
-        if ($glimpse['type'] == Lexer::T_DOT) {
+        if ($glimpse['type'] === Lexer::T_DOT) {
             return $this->SingleValuedPathExpression();
         }
 
-        $token = $this->_lexer->lookahead;
-        $identVariable = $this->IdentificationVariable();
+        // Still need to decide between IdentificationVariable or ResultVariable
+        $lookaheadValue = $this->_lexer->lookahead['value'];
 
-        if ( ! isset($this->_queryComponents[$identVariable])) {
-            $this->semanticalError('Cannot group by undefined identification variable.');
+        if ( ! isset($this->_queryComponents[$lookaheadValue])) {
+            $this->semanticalError('Cannot group by undefined identification or result variable.');
         }
 
-        return $identVariable;
+        return (isset($this->_queryComponents[$lookaheadValue]['metadata']))
+            ? $this->IdentificationVariable()
+            : $this->ResultVariable();
     }
 
     /**
@@ -2633,7 +2635,7 @@ class Parser
             $isDistinct = true;
         }
 
-        $pathExp = ($lookaheadType === Lexer::T_COUNT) 
+        $pathExp = ($lookaheadType === Lexer::T_COUNT)
             ? $this->SingleValuedPathExpression()
             : $this->SimpleArithmeticExpression();
 
diff --git a/lib/Doctrine/ORM/Query/SqlWalker.php b/lib/Doctrine/ORM/Query/SqlWalker.php
index 3b58dfba2..c12ea0690 100644
--- a/lib/Doctrine/ORM/Query/SqlWalker.php
+++ b/lib/Doctrine/ORM/Query/SqlWalker.php
@@ -1014,6 +1014,8 @@ class SqlWalker implements TreeWalker
 
                 $sql .= $col . ' AS ' . $columnAlias;
 
+                $this->_scalarResultAliasMap[$resultAlias] = $columnAlias;
+
                 if ( ! $hidden) {
                     $this->_rsm->addScalarResult($columnAlias, $resultAlias);
                     $this->_scalarFields[$dqlAlias][$fieldName] = $columnAlias;
@@ -1103,6 +1105,8 @@ class SqlWalker implements TreeWalker
 
                     $sqlParts[] = $col . ' AS '. $columnAlias;
 
+                    $this->_scalarResultAliasMap[$resultAlias][] = $columnAlias;
+
                     $this->_rsm->addFieldResult($dqlAlias, $columnAlias, $fieldName, $class->name);
                 }
 
@@ -1132,6 +1136,8 @@ class SqlWalker implements TreeWalker
 
                             $sqlParts[] = $col . ' AS ' . $columnAlias;
 
+                            $this->_scalarResultAliasMap[$resultAlias][] = $columnAlias;
+
                             $this->_rsm->addFieldResult($dqlAlias, $columnAlias, $fieldName, $subClassName);
                         }
                     }
@@ -1319,25 +1325,7 @@ class SqlWalker implements TreeWalker
         $sqlParts = array();
 
         foreach ($groupByClause->groupByItems AS $groupByItem) {
-            if ( ! is_string($groupByItem)) {
-                $sqlParts[] = $this->walkGroupByItem($groupByItem);
-
-                continue;
-            }
-
-            foreach ($this->_queryComponents[$groupByItem]['metadata']->fieldNames AS $field) {
-                $item       = new AST\PathExpression(AST\PathExpression::TYPE_STATE_FIELD, $groupByItem, $field);
-                $item->type = AST\PathExpression::TYPE_STATE_FIELD;
-                $sqlParts[] = $this->walkGroupByItem($item);
-            }
-            
-            foreach ($this->_queryComponents[$groupByItem]['metadata']->associationMappings AS $mapping) {
-                if ($mapping['isOwningSide'] && $mapping['type'] & ClassMetadataInfo::TO_ONE) {
-                    $item       = new AST\PathExpression(AST\PathExpression::TYPE_SINGLE_VALUED_ASSOCIATION, $groupByItem, $mapping['fieldName']);
-                    $item->type = AST\PathExpression::TYPE_SINGLE_VALUED_ASSOCIATION;
-                    $sqlParts[] = $this->walkGroupByItem($item);
-                }
-            }
+            $sqlParts[] = $this->walkGroupByItem($groupByItem);
         }
 
         return ' GROUP BY ' . implode(', ', $sqlParts);
@@ -1349,9 +1337,38 @@ class SqlWalker implements TreeWalker
      * @param GroupByItem
      * @return string The SQL.
      */
-    public function walkGroupByItem(AST\PathExpression $pathExpr)
+    public function walkGroupByItem($groupByItem)
     {
-        return $this->walkPathExpression($pathExpr);
+        // StateFieldPathExpression
+        if ( ! is_string($groupByItem)) {
+            return $this->walkPathExpression($groupByItem);
+        }
+
+        // ResultVariable
+        if (isset($this->_queryComponents[$groupByItem]['resultVariable'])) {
+            return $this->walkResultVariable($groupByItem);
+        }
+
+        // IdentificationVariable
+        $sqlParts = array();
+
+        foreach ($this->_queryComponents[$groupByItem]['metadata']->fieldNames AS $field) {
+            $item       = new AST\PathExpression(AST\PathExpression::TYPE_STATE_FIELD, $groupByItem, $field);
+            $item->type = AST\PathExpression::TYPE_STATE_FIELD;
+
+            $sqlParts[] = $this->walkPathExpression($item);
+        }
+
+        foreach ($this->_queryComponents[$groupByItem]['metadata']->associationMappings AS $mapping) {
+            if ($mapping['isOwningSide'] && $mapping['type'] & ClassMetadataInfo::TO_ONE) {
+                $item       = new AST\PathExpression(AST\PathExpression::TYPE_SINGLE_VALUED_ASSOCIATION, $groupByItem, $mapping['fieldName']);
+                $item->type = AST\PathExpression::TYPE_SINGLE_VALUED_ASSOCIATION;
+
+                $sqlParts[] = $this->walkPathExpression($item);
+            }
+        }
+
+        return implode(', ', $sqlParts);
     }
 
     /**
@@ -1997,4 +2014,21 @@ class SqlWalker implements TreeWalker
             ? $this->_conn->quote($stringPrimary)
             : $stringPrimary->dispatch($this);
     }
+
+    /**
+     * Walks down a ResultVriable that represents an AST node, thereby generating the appropriate SQL.
+     *
+     * @param string $resultVariable
+     * @return string The SQL.
+     */
+    public function walkResultVariable($resultVariable)
+    {
+        $resultAlias = $this->_scalarResultAliasMap[$resultVariable];
+
+        if (is_array($resultAlias)) {
+            return implode(', ', $resultAlias);
+        }
+
+        return $resultAlias;
+    }
 }
diff --git a/lib/Doctrine/ORM/Query/TreeWalker.php b/lib/Doctrine/ORM/Query/TreeWalker.php
index 4bbe963a6..84628981c 100644
--- a/lib/Doctrine/ORM/Query/TreeWalker.php
+++ b/lib/Doctrine/ORM/Query/TreeWalker.php
@@ -168,7 +168,7 @@ interface TreeWalker
      * @param GroupByItem
      * @return string The SQL.
      */
-    function walkGroupByItem(AST\PathExpression $pathExpr);
+    function walkGroupByItem($groupByItem);
 
     /**
      * Walks down an UpdateStatement AST node, thereby generating the appropriate SQL.
@@ -394,6 +394,14 @@ interface TreeWalker
      */
     function walkPathExpression($pathExpr);
 
+    /**
+     * Walks down an ResultVariable AST node, thereby generating the appropriate SQL.
+     *
+     * @param string $resultVariable
+     * @return string The SQL.
+     */
+    function walkResultVariable($resultVariable);
+
     /**
      * Gets an executor that can be used to execute the result of this walker.
      *
diff --git a/lib/Doctrine/ORM/Query/TreeWalkerAdapter.php b/lib/Doctrine/ORM/Query/TreeWalkerAdapter.php
index ca2a49520..530b98c50 100644
--- a/lib/Doctrine/ORM/Query/TreeWalkerAdapter.php
+++ b/lib/Doctrine/ORM/Query/TreeWalkerAdapter.php
@@ -24,7 +24,7 @@ namespace Doctrine\ORM\Query;
 /**
  * An adapter implementation of the TreeWalker interface. The methods in this class
  * are empty. This class exists as convenience for creating tree walkers.
- * 
+ *
  * @author Roman Borschel <roman@code-factory.org>
  * @since 2.0
  */
@@ -33,7 +33,7 @@ abstract class TreeWalkerAdapter implements TreeWalker
     private $_query;
     private $_parserResult;
     private $_queryComponents;
-    
+
     /**
      * {@inheritdoc}
      */
@@ -71,7 +71,7 @@ abstract class TreeWalkerAdapter implements TreeWalker
     {
         return $this->_parserResult;
     }
-    
+
     /**
      * Walks down a SelectStatement AST node, thereby generating the appropriate SQL.
      *
@@ -202,7 +202,7 @@ abstract class TreeWalkerAdapter implements TreeWalker
      * @param GroupByItem
      * @return string The SQL.
      */
-    public function walkGroupByItem(AST\PathExpression $pathExpr) {}
+    public function walkGroupByItem($groupByItem) {}
 
     /**
      * Walks down an UpdateStatement AST node, thereby generating the appropriate SQL.
@@ -291,7 +291,7 @@ abstract class TreeWalkerAdapter implements TreeWalker
      * @return string The SQL.
      */
     public function walkExistsExpression($existsExpr) {}
-    
+
     /**
      * Walks down a CollectionMemberExpression AST node, thereby generating the appropriate SQL.
      *
@@ -427,10 +427,18 @@ abstract class TreeWalkerAdapter implements TreeWalker
      * @return string The SQL.
      */
     public function walkPathExpression($pathExpr) {}
-    
+
+    /**
+     * Walks down an ResultVariable AST node, thereby generating the appropriate SQL.
+     *
+     * @param string $resultVariable
+     * @return string The SQL.
+     */
+    public function walkResultVariable($resultVariable) {}
+
     /**
      * Gets an executor that can be used to execute the result of this walker.
-     * 
+     *
      * @return AbstractExecutor
      */
     public function getExecutor($AST) {}
diff --git a/lib/Doctrine/ORM/Query/TreeWalkerChain.php b/lib/Doctrine/ORM/Query/TreeWalkerChain.php
index 1fc197783..d3891a114 100644
--- a/lib/Doctrine/ORM/Query/TreeWalkerChain.php
+++ b/lib/Doctrine/ORM/Query/TreeWalkerChain.php
@@ -25,7 +25,7 @@ namespace Doctrine\ORM\Query;
  * Represents a chain of tree walkers that modify an AST and finally emit output.
  * Only the last walker in the chain can emit output. Any previous walkers can modify
  * the AST to influence the final output produced by the last walker.
- * 
+ *
  * @author Roman Borschel <roman@code-factory.org>
  * @since 2.0
  */
@@ -39,7 +39,7 @@ class TreeWalkerChain implements TreeWalker
     private $_parserResult;
     /** The query components of the original query (the "symbol table") that was produced by the Parser. */
     private $_queryComponents;
-    
+
     /**
      * @inheritdoc
      */
@@ -49,17 +49,17 @@ class TreeWalkerChain implements TreeWalker
         $this->_parserResult = $parserResult;
         $this->_queryComponents = $queryComponents;
     }
-    
+
     /**
      * Adds a tree walker to the chain.
-     * 
+     *
      * @param string $walkerClass The class of the walker to instantiate.
      */
     public function addTreeWalker($walkerClass)
     {
         $this->_walkers[] = new $walkerClass($this->_query, $this->_parserResult, $this->_queryComponents);
     }
-    
+
     /**
      * Walks down a SelectStatement AST node, thereby generating the appropriate SQL.
      *
@@ -270,10 +270,10 @@ class TreeWalkerChain implements TreeWalker
      * @param GroupByItem
      * @return string The SQL.
      */
-    public function walkGroupByItem(AST\PathExpression $pathExpr)
+    public function walkGroupByItem($groupByItem)
     {
         foreach ($this->_walkers as $walker) {
-            $walker->walkGroupByItem($pathExpr);
+            $walker->walkGroupByItem($groupByItem);
         }
     }
 
@@ -419,7 +419,7 @@ class TreeWalkerChain implements TreeWalker
             $walker->walkExistsExpression($existsExpr);
         }
     }
-    
+
     /**
      * Walks down a CollectionMemberExpression AST node, thereby generating the appropriate SQL.
      *
@@ -640,10 +640,23 @@ class TreeWalkerChain implements TreeWalker
             $walker->walkPathExpression($pathExpr);
         }
     }
-    
+
+    /**
+     * Walks down an ResultVariable AST node, thereby generating the appropriate SQL.
+     *
+     * @param string $resultVariable
+     * @return string The SQL.
+     */
+    public function walkResultVariable($resultVariable)
+    {
+        foreach ($this->_walkers as $walker) {
+            $walker->walkResultVariable($resultVariable);
+        }
+    }
+
     /**
      * Gets an executor that can be used to execute the result of this walker.
-     * 
+     *
      * @return AbstractExecutor
      */
     public function getExecutor($AST)
diff --git a/tests/Doctrine/Tests/ORM/Query/SelectSqlGenerationTest.php b/tests/Doctrine/Tests/ORM/Query/SelectSqlGenerationTest.php
index ceb1a3729..50de767db 100644
--- a/tests/Doctrine/Tests/ORM/Query/SelectSqlGenerationTest.php
+++ b/tests/Doctrine/Tests/ORM/Query/SelectSqlGenerationTest.php
@@ -40,7 +40,14 @@ class SelectSqlGenerationTest extends \Doctrine\Tests\OrmTestCase
                 $query->setHint($name, $value);
             }
 
-            parent::assertEquals($sqlToBeConfirmed, $query->getSQL());
+            $sqlGenerated = $query->getSQL();
+
+            parent::assertEquals(
+                $sqlToBeConfirmed,
+                $sqlGenerated,
+                sprintf('"%s" is not equal of "%s"', $sqlGenerated, $sqlToBeConfirmed)
+            );
+
             $query->free();
         } catch (\Exception $e) {
             $this->fail($e->getMessage() ."\n".$e->getTraceAsString());
@@ -1302,7 +1309,7 @@ class SelectSqlGenerationTest extends \Doctrine\Tests\OrmTestCase
             "SELECT d0_.article_id AS article_id0, d0_.title AS title1 FROM DDC117Article d0_ WHERE EXISTS (SELECT d1_.source_id, d1_.target_id FROM DDC117Reference d1_ WHERE d1_.source_id = d0_.article_id)"
         );
     }
-    
+
     /**
      * @group DDC-1474
      */
@@ -1312,13 +1319,13 @@ class SelectSqlGenerationTest extends \Doctrine\Tests\OrmTestCase
             'SELECT - e.value AS value, e.id FROM ' . __NAMESPACE__ . '\DDC1474Entity e',
             'SELECT -d0_.value AS sclr0, d0_.id AS id1 FROM DDC1474Entity d0_'
         );
-        
+
         $this->assertSqlGeneration(
             'SELECT e.id, + e.value AS value FROM ' . __NAMESPACE__ . '\DDC1474Entity e',
             'SELECT d0_.id AS id0, +d0_.value AS sclr1 FROM DDC1474Entity d0_'
         );
     }
-    
+
      /**
      * @group DDC-1430
      */
@@ -1328,13 +1335,35 @@ class SelectSqlGenerationTest extends \Doctrine\Tests\OrmTestCase
             'SELECT u FROM Doctrine\Tests\Models\CMS\CmsUser u GROUP BY u',
             'SELECT c0_.id AS id0, c0_.status AS status1, c0_.username AS username2, c0_.name AS name3 FROM cms_users c0_ GROUP BY c0_.id, c0_.status, c0_.username, c0_.name, c0_.email_id'
         );
-        
+
         $this->assertSqlGeneration(
             'SELECT e FROM Doctrine\Tests\Models\CMS\CmsEmployee e GROUP BY e',
             'SELECT c0_.id AS id0, c0_.name AS name1 FROM cms_employees c0_ GROUP BY c0_.id, c0_.name, c0_.spouse_id'
         );
     }
 
+    /**
+     * @group DDC-1236
+     */
+    public function testGroupBySupportsResultVariable()
+    {
+        $this->assertSqlGeneration(
+            'SELECT u, u.status AS st FROM Doctrine\Tests\Models\CMS\CmsUser u GROUP BY st',
+            'SELECT c0_.id AS id0, c0_.status AS status1, c0_.username AS username2, c0_.name AS name3, c0_.status AS status4 FROM cms_users c0_ GROUP BY status4'
+        );
+    }
+
+    /**
+     * @group DDC-1236
+     */
+    public function testGroupBySupportsIdentificationVariable()
+    {
+        $this->assertSqlGeneration(
+            'SELECT u AS user FROM Doctrine\Tests\Models\CMS\CmsUser u GROUP BY user',
+            'SELECT c0_.id AS id0, c0_.status AS status1, c0_.username AS username2, c0_.name AS name3 FROM cms_users c0_ GROUP BY id0, status1, username2, name3'
+        );
+    }
+
     public function testCustomTypeValueSql()
     {
         if (DBALType::hasType('negative_to_positive')) {
@@ -1441,19 +1470,19 @@ class DDC1474Entity
 {
 
     /**
-     * @Id 
+     * @Id
      * @Column(type="integer")
      * @GeneratedValue()
      */
     protected $id;
 
     /**
-     * @column(type="float") 
+     * @column(type="float")
      */
     private $value;
 
     /**
-     * @param string $float 
+     * @param string $float
      */
     public function __construct($float)
     {
@@ -1469,7 +1498,7 @@ class DDC1474Entity
     }
 
     /**
-     * @return float 
+     * @return float
      */
     public function getValue()
     {
@@ -1477,7 +1506,7 @@ class DDC1474Entity
     }
 
     /**
-     * @param float $value 
+     * @param float $value
      */
     public function setValue($value)
     {