7 * This source file is subject to the new BSD license that is bundled
8 * with this package in the file LICENSE.txt.
9 * If you did not receive a copy of the license and are unable to
10 * obtain it through the world-wide-web, please send an email
11 * to kontakt@beberlei.de so I can send you a copy immediately.
14 namespace Doctrine\ORM\Tools\Pagination;
16 use Doctrine\ORM\Query\TreeWalkerAdapter,
17 Doctrine\ORM\Query\AST\SelectStatement,
18 Doctrine\ORM\Query\AST\SelectExpression,
19 Doctrine\ORM\Query\AST\PathExpression,
20 Doctrine\ORM\Query\AST\AggregateExpression;
23 * Replaces the selectClause of the AST with a COUNT statement
25 * @category DoctrineExtensions
26 * @package DoctrineExtensions\Paginate
27 * @author David Abdemoulaie <dave@hobodave.com>
28 * @copyright Copyright (c) 2010 David Abdemoulaie (http://hobodave.com/)
29 * @license http://hobodave.com/license.txt New BSD License
31 class CountWalker extends TreeWalkerAdapter
34 * Distinct mode hint name
36 const HINT_DISTINCT = 'doctrine_paginator.distinct';
39 * Walks down a SelectStatement AST node, modifying it to retrieve a COUNT
41 * @param SelectStatement $AST
44 public function walkSelectStatement(SelectStatement $AST)
46 if ($AST->havingClause) {
47 throw new \RuntimeException('Cannot count query that uses a HAVING clause. Use the output walkers for pagination');
50 $rootComponents = array();
51 foreach ($this->_getQueryComponents() as $dqlAlias => $qComp) {
52 $isParent = array_key_exists('parent', $qComp)
53 && $qComp['parent'] === null
54 && $qComp['nestingLevel'] == 0
57 $rootComponents[] = array($dqlAlias => $qComp);
60 if (count($rootComponents) > 1) {
61 throw new \RuntimeException("Cannot count query which selects two FROM components, cannot make distinction");
63 $root = reset($rootComponents);
64 $parentName = key($root);
65 $parent = current($root);
66 $identifierFieldName = $parent['metadata']->getSingleIdentifierFieldName();
68 $pathType = PathExpression::TYPE_STATE_FIELD;
69 if (isset($parent['metadata']->associationMappings[$identifierFieldName])) {
70 $pathType = PathExpression::TYPE_SINGLE_VALUED_ASSOCIATION;
73 $pathExpression = new PathExpression(
74 PathExpression::TYPE_STATE_FIELD | PathExpression::TYPE_SINGLE_VALUED_ASSOCIATION, $parentName,
77 $pathExpression->type = $pathType;
79 $distinct = $this->_getQuery()->getHint(self::HINT_DISTINCT);
80 $AST->selectClause->selectExpressions = array(
82 new AggregateExpression('count', $pathExpression, $distinct), null
86 // ORDER BY is not needed, only increases query execution through unnecessary sorting.
87 $AST->orderByClause = null;