DbConnectionPool::getDbConnectionClassNameByType

private function getDbConnectionClassNameByType($connectionType)
{
	switch ($connectionType)
	{
		case 'mysql':
			$className = "\Bitrix\Main\DB\MysqliDbConnection";
			if (!extension_loaded("mysqli"))
				$className = "\Bitrix\Main\DB\MysqlDbConnection";
			break;
		case 'oracle':
			$className = "\Bitrix\Main\DB\OracleDbConnection";
			break;
		case 'mssql':
			$className = "\Bitrix\Main\DB\MssqlDbConnection";
			break;
		case 'mssql_native':
			$className = "\Bitrix\Main\DB\MssqlNativeDbConnection";
			break;
		default:
			throw new BitrixMainConfigConfigurationException("Database type mismatch");
	}

	return $className;
}