Adding ORDER support for UNION queries (#86)

Author: mhtghn

src/SQLParser/Query/StatementFactory.php

@@ -96,7 +96,15 @@ public static function toObject(array $desc)
             /** @var Select[] $selects */
             $selects = array_map([self::class, 'toObject'], $desc['UNION']);
 
-            return new Union($selects);
+            $union = new Union($selects);
+
+            if (isset($desc['0']) && isset($desc['0']['ORDER'])) {
+                $order = NodeFactory::mapArrayToNodeObjectList($desc['0']['ORDER']);
+                $order = NodeFactory::simplify($order);
+                $union->setOrder($order);
+            }
+
+            return $union;
         } else {
             throw new \BadMethodCallException('Unknown query');
         }

src/SQLParser/Query/Union.php

@@ -34,6 +34,29 @@ public function __construct(array $selects)
         $this->selects = $selects;
     }
 
+    /** @var NodeInterface[]|NodeInterface */
+    private $order;
+
+    /**
+     * Returns the list of order statements.
+     *
+     * @return NodeInterface[]|NodeInterface
+     */
+    public function getOrder()
+    {
+        return $this->order;
+    }
+
+    /**
+     * Sets the list of order statements.
+     *
+     * @param NodeInterface[]|NodeInterface $order
+     */
+    public function setOrder($order): void
+    {
+        $this->order = $order;
+    }
+
     /**
      * @param MoufManager $moufManager
      *
@@ -43,6 +66,7 @@ public function toInstanceDescriptor(MoufManager $moufManager)
     {
         $instanceDescriptor = $moufManager->createInstance(get_called_class());
         $instanceDescriptor->getProperty('selects')->setValue(NodeFactory::nodeToInstanceDescriptor($this->selects, $moufManager));
+        $instanceDescriptor->getProperty('order')->setValue(NodeFactory::nodeToInstanceDescriptor($this->order, $moufManager));
 
         return $instanceDescriptor;
     }
@@ -59,6 +83,7 @@ public function overwriteInstanceDescriptor($name, MoufManager $moufManager)
         //$name = $moufManager->findInstanceName($this);
         $instanceDescriptor = $moufManager->getInstanceDescriptor($name);
         $instanceDescriptor->getProperty('selects')->setValue(NodeFactory::nodeToInstanceDescriptor($this->selects, $moufManager));
+        $instanceDescriptor->getProperty('order')->setValue(NodeFactory::nodeToInstanceDescriptor($this->order, $moufManager));
 
         return $instanceDescriptor;
     }
@@ -80,7 +105,14 @@ public function toSql(array $parameters, AbstractPlatform $platform, int $indent
             return $select->toSql($parameters, $platform, $indent, $conditionsMode, $extrapolateParameters);
         }, $this->selects);
 
-        $sql = implode(' UNION ', $selectsSql);
+        $sql = '(' . implode(') UNION (', $selectsSql) . ')';
+
+        if (!empty($this->order)) {
+            $order = NodeFactory::toSql($this->order, $platform, $parameters, ',', false, $indent + 2, $conditionsMode, $extrapolateParameters);
+            if ($order) {
+                $sql .= "\nORDER BY ".$order;
+            }
+        }
 
         return $sql;
     }
@@ -99,27 +131,37 @@ public function walk(VisitorInterface $visitor)
         }
         if ($result !== NodeTraverser::DONT_TRAVERSE_CHILDREN) {
             $this->walkChildren($this->selects, $visitor);
+            $this->walkChildren($this->order, $visitor);
         }
 
         return $visitor->leaveNode($node);
     }
 
     /**
-     * @param array<Select|null> $children
+     * @param array<Select|NodeInterface|null>|NodeInterface|null $children
      * @param VisitorInterface $visitor
      */
-    private function walkChildren(array &$children, VisitorInterface $visitor): void
+    private function walkChildren(&$children, VisitorInterface $visitor): void
     {
         if ($children) {
-            foreach ($children as $key => $operand) {
-                if ($operand) {
-                    $result2 = $operand->walk($visitor);
-                    if ($result2 === NodeTraverser::REMOVE_NODE) {
-                        unset($children[$key]);
-                    } elseif ($result2 instanceof NodeInterface) {
-                        $children[$key] = $result2;
+            if (is_array($children)) {
+                foreach ($children as $key => $operand) {
+                    if ($operand) {
+                        $result2 = $operand->walk($visitor);
+                        if ($result2 === NodeTraverser::REMOVE_NODE) {
+                            unset($children[$key]);
+                        } elseif ($result2 instanceof NodeInterface) {
+                            $children[$key] = $result2;
+                        }
                     }
                 }
+            } else {
+                $result2 = $children->walk($visitor);
+                if ($result2 === NodeTraverser::REMOVE_NODE) {
+                    $children = null;
+                } elseif ($result2 instanceof NodeInterface) {
+                    $children = $result2;
+                }
             }
         }
     }

tests/Mouf/Database/MagicQueryTest.php

@@ -186,7 +186,7 @@ public function testStandardSelect()
         $this->assertEquals('SELECT COUNT(DISTINCT a, b) FROM users', self::simplifySql($magicQuery->build($sql)));
 
         $sql = 'SELECT a FROM users UNION SELECT a FROM users';
-        $this->assertEquals('SELECT a FROM users UNION SELECT a FROM users', self::simplifySql($magicQuery->build($sql)));
+        $this->assertEquals('(SELECT a FROM users) UNION (SELECT a FROM users)', self::simplifySql($magicQuery->build($sql)));
 
         $sql = 'SELECT a FROM users u, users u2';
         $this->assertEquals('SELECT a FROM users u CROSS JOIN users u2', self::simplifySql($magicQuery->build($sql)));
@@ -478,4 +478,34 @@ public function testPrepareStatementCache(): void
         $this->assertEquals('SELECT * FROM users WHERE 0 <> 0', self::simplifySql($magicQuery->buildPreparedStatement('SELECT * FROM users WHERE id IN :users', ['users' => []])));
         $this->assertEquals('SELECT * FROM users WHERE id IN (:users)', self::simplifySql($magicQuery->buildPreparedStatement('SELECT * FROM users WHERE id IN :users', ['users' => [1]])));
     }
+
+    public function testUnionAndOrderBy(): void
+    {
+        $magicQuery = new MagicQuery(null, new ArrayCache());
+
+        $query = '(SELECT id FROM users) UNION (SELECT id FROM users) ORDER BY users.id ASC';
+
+        $this->assertEquals(
+            '(SELECT id FROM users) UNION (SELECT id FROM users) ORDER BY users.id ASC',
+            self::simplifySql($magicQuery->buildPreparedStatement($query))
+        );
+
+        $query = '(SELECT id FROM users) UNION (SELECT id FROM users ORDER BY users.id ASC)';
+        $this->assertEquals(
+            '(SELECT id FROM users) UNION (SELECT id FROM users ORDER BY users.id ASC)',
+            self::simplifySql($magicQuery->buildPreparedStatement($query))
+        );
+
+        $query = '(SELECT id FROM users ORDER BY users.id ASC) UNION (SELECT id FROM users)';
+        $this->assertEquals(
+            '(SELECT id FROM users ORDER BY users.id ASC) UNION (SELECT id FROM users)',
+            self::simplifySql($magicQuery->buildPreparedStatement($query))
+        );
+
+        $query = 'SELECT id FROM users UNION SELECT id FROM users ORDER BY users.id ASC';
+        $this->assertEquals(
+            '(SELECT id FROM users) UNION (SELECT id FROM users) ORDER BY users.id ASC',
+            self::simplifySql($magicQuery->buildPreparedStatement($query))
+        );
+    }
 }