./x.php -> contains dbdriver

./system/database/DB.php -> contains dbdriver

./system/database/DB_driver.php -> contains dbdriver

./system/database/drivers/mysqli/mysqli_driver.php -> contains dbdriver

./system/database/drivers/odbc/odbc_driver.php -> contains dbdriver

./system/database/drivers/sqlsrv/sqlsrv_driver.php -> contains dbdriver

./system/database/drivers/sqlite/sqlite_driver.php -> contains dbdriver

./system/database/drivers/mssql/mssql_driver.php -> contains dbdriver

./system/database/drivers/oci8/oci8_driver.php -> contains dbdriver

./system/database/drivers/mysql/mysql_driver.php -> contains dbdriver

./system/database/drivers/postgre/postgre_driver.php -> contains dbdriver

./system/database/drivers/cubrid/cubrid_driver.php -> contains dbdriver

./system/database/drivers/pdo/pdo_driver.php -> contains dbdriver

./system/core/Loader.php -> contains dbdriver

./application/config/database.php -> contains dbdriver