Breaking: #75454 - LocalConfiguration DB config structure has changed

See Issue #75454


To provide support for multiple database connections and remapping tables to different database systems within the TYPO3 Core the configuration format for database connections in LocalConfiguration.php / $GLOBALS['TYPO3_CONF_VARS']['DB'] has changed.

The new configuration array structure:

'DB' => [
        'Connections' => [
                'Default' => [
                        'driver' => 'mysqli',
                        'dbname' => 'typo3_database',
                        'password' => 'typo3',
                        'host' => '',
                        'port' => 3306,
                        'user' => 'typo3',
                        'socket' => ''
                        'charset' => 'utf-8',

Be aware that besides the deeper nesting below 'Connections/Default' some of the configuration keys have been renamed. It is required to provide the new configuration key driver with a value of mysqli explicitly.

The following table lists the changed configuration keys and the appropriate values if these have changed.

Old name New name
DB/username DB/Connections/Default/user
DB/password DB/Connections/Default/password
DB/host DB/Connections/Default/host
DB/port DB/Connections/Default/port
DB/socket DB/Connections/Default/unix_socket
DB/database DB/Connections/Default/dbname
SYS/setDBinit DB/Connections/Default/initCommands
SYS/no_pconnect DB/Connections/Default/persistentConnection
SYS/dbClientCompress DB/Connections/Default/driverOptions Valid values for MySQLi connections: 0 compression disabled 32 compression enabled


Connections to the database will fail with an exception until the configuration has been migrated to the new structure.

Affected Installations

All Installations


The Install Tool will migrate the configuration information for the default connection to the new format. Installations overriding the database configuration using AdditionalConfiguration.php or other means need to ensure the new format is being used.