<?php
declare(strict_types=1);
namespace PhpMyAdmin\Utils;
use function strtolower;
use function strtoupper;
use function substr;
use function version_compare;
final class ForeignKey
{
/**
* Verifies if this table's engine supports foreign keys
*
* @param string $engine engine
*/
public static function isSupported($engine): bool
{
global $dbi;
$engine = strtoupper((string) $engine);
if (($engine === 'INNODB') || ($engine === 'PBXT')) {
return true;
}
if ($engine === 'NDBCLUSTER' || $engine === 'NDB') {
$ndbver = strtolower(
$dbi->fetchValue('SELECT @@ndb_version_string') ?: ''
);
if (substr($ndbver, 0, 4) === 'ndb-') {
$ndbver = substr($ndbver, 4);
}
return version_compare($ndbver, '7.3', '>=');
}
return false;
}
/**
* Is Foreign key check enabled?
*/
public static function isCheckEnabled(): bool
{
global $dbi;
if ($GLOBALS['cfg']['DefaultForeignKeyChecks'] === 'enable') {
return true;
}
if ($GLOBALS['cfg']['DefaultForeignKeyChecks'] === 'disable') {
return false;
}
return $dbi->getVariable('FOREIGN_KEY_CHECKS') === 'ON';
}
/**
* Handle foreign key check request
*/
public static function handleDisableCheckInit(): bool
{
global $dbi;
$defaultCheckValue = $dbi->getVariable('FOREIGN_KEY_CHECKS') === 'ON';
if (isset($_REQUEST['fk_checks'])) {
if (empty($_REQUEST['fk_checks'])) {
// Disable foreign key checks
$dbi->setVariable('FOREIGN_KEY_CHECKS', 'OFF');
} else {
// Enable foreign key checks
$dbi->setVariable('FOREIGN_KEY_CHECKS', 'ON');
}
}
return $defaultCheckValue;
}
/**
* Cleanup changes done for foreign key check
*
* @param bool $defaultCheckValue original value for 'FOREIGN_KEY_CHECKS'
*/
public static function handleDisableCheckCleanup(bool $defaultCheckValue): void
{
global $dbi;
$dbi->setVariable('FOREIGN_KEY_CHECKS', $defaultCheckValue ? 'ON' : 'OFF');
}
}