<?php
/**
* CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
* Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
*
* Licensed under The MIT License
* For full copyright and license information, please see the LICENSE.txt
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
* @link https://cakephp.org CakePHP(tm) Project
* @since 3.0.0
* @license https://opensource.org/licenses/mit-license.php MIT License
*/
namespace Cake\Database\Dialect;
use Cake\Database\Expression\IdentifierExpression;
use Cake\Database\Expression\QueryExpression;
use Cake\Database\Expression\TupleComparison;
use Cake\Database\Query;
/**
* Provides a translator method for tuple comparisons
*
* @internal
*/
trait TupleComparisonTranslatorTrait
{
/**
* Receives a TupleExpression and changes it so that it conforms to this
* SQL dialect.
*
* It transforms expressions looking like '(a, b) IN ((c, d), (e, f))' into an
* equivalent expression of the form '((a = c) AND (b = d)) OR ((a = e) AND (b = f))'.
*
* It can also transform transform expressions where the right hand side is a query
* selecting the same amount of columns as the elements in the left hand side of
* the expression:
*
* (a, b) IN (SELECT c, d FROM a_table) is transformed into
*
* 1 = (SELECT 1 FROM a_table WHERE (a = c) AND (b = d))
*
* @param \Cake\Database\Expression\TupleComparison $expression The expression to transform
* @param \Cake\Database\Query $query The query to update.
* @return void
*/
protected function _transformTupleComparison(TupleComparison $expression, $query)
{
$fields = $expression->getField();
if (!is_array($fields)) {
return;
}
$value = $expression->getValue();
$op = $expression->getOperator();
$true = new QueryExpression('1');
if ($value instanceof Query) {
$selected = array_values($value->clause('select'));
foreach ($fields as $i => $field) {
$value->andWhere([$field . " $op" => new IdentifierExpression($selected[$i])]);
}
$value->select($true, true);
$expression->setField($true);
$expression->setOperator('=');
return;
}
$surrogate = $query->getConnection()
->newQuery()
->select($true);
if (!is_array(current($value))) {
$value = [$value];
}
$conditions = ['OR' => []];
foreach ($value as $tuple) {
$item = [];
foreach (array_values($tuple) as $i => $value) {
$item[] = [$fields[$i] => $value];
}
$conditions['OR'][] = $item;
}
$surrogate->where($conditions);
$expression->setField($true);
$expression->setValue($surrogate);
$expression->setOperator('=');
}
}