Part-DB.Part-DB-server/src/DataTables/Adapters/CustomFetchJoinORMAdapter.php

55 lines
2.4 KiB
PHP

<?php
declare(strict_types=1);
/*
* This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
*
* Copyright (C) 2019 - 2023 Jan Böhmer (https://github.com/jbtronics)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published
* by the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
namespace App\DataTables\Adapters;
use Doctrine\ORM\QueryBuilder;
use Doctrine\ORM\Tools\Pagination\Paginator;
use Omines\DataTablesBundle\Adapter\Doctrine\FetchJoinORMAdapter;
/**
* This class is a workaround for a bug (or edge case behavior) in the FetchJoinORMAdapter or better the used Paginator
* and CountOutputWalker.
* If the query contains multiple GROUP BY clauses, the result of the count query is wrong, as some lines are counted
* multiple times. This is because the CountOutputWalker does not use DISTINCT in the count query, if it contains a GROUP BY.
*
* We work around this by removing the GROUP BY clause from the query, and only adding the first root alias as GROUP BY (the part table).
* This way we get the correct count, without breaking the query (we need a GROUP BY for the HAVING clauses).
*
* As a side effect this also seems to improve the performance of the count query a bit (which makes up a lot of the total query time).
*/
class CustomFetchJoinORMAdapter extends FetchJoinORMAdapter
{
public function getCount(QueryBuilder $queryBuilder, $identifier): int
{
$qb_without_group_by = clone $queryBuilder;
//Remove the groupBy clause from the query for the count
//And add the root alias as group by, so we can use HAVING clauses
$qb_without_group_by->resetDQLPart('groupBy');
$qb_without_group_by->addGroupBy($queryBuilder->getRootAliases()[0]);
$paginator = new Paginator($qb_without_group_by);
return $paginator->count();
}
}