Converting Database Type


SQLite is good for testing ownCloud, as well as small, single-user, ownCloud servers. But, it does not scale for large, multi-user sites. If you have an existing ownCloud installation which uses SQLite, and you want to convert to a better performing database, such as MySQL, MariaDB or PostgreSQL, you can use the ownCloud command line tool: occ.

ownCloud Enterprise edition does not support SQLite.


Add the following to your ownCloud config/config.php:

'mysql.utf8mb4' => true,

Add, or adjust, the following in /etc/mysql/mariadb.conf.d/50-server.cnf:

You can do the same for MySQL by replacing mariadb.conf.d/50-server.cnf with mysql.conf.d/mysqld.cnf.
key_buffer_size         = 32M
table_cache             = 400
query_cache_size        = 128M

#in InnoDB:
innodb_log_buffer_size = 128M
innodb_io_capacity = 500
character-set-server  = utf8mb4
collation-server      = utf8mb4_general_ci

Restart the Database Server

When you have changed the database parameters, restart your database by running following command:

sudo service mysql restart

Run the conversion

After you have restarted the database, run the following occ command in your ownCloud root folder, to convert the database to the new format:

sudo -u www-data ./occ db:convert-type [options] type username hostname database

The converter searches for apps in your configured app folders and uses the schema definitions in the apps to create the new table. As a result, tables of removed apps will not be converted — even with option --all-apps For example:

sudo -u www-data ./occ db:convert-type --all-apps mysql oc_mysql_user new_db_name

To successfully proceed with the conversion, you must type yes when prompted with the question Continue with the conversion? On success the converter will automatically configure the new database in your ownCloud config config.php.

Unconvertible Tables

If you updated your ownCloud installation then the old tables, which are not used anymore, might still exist. The converter will tell you which ones.

The following tables will not be converted:

You can ignore these tables. Here is a list of known old tables:

  • oc_calendar_calendars

  • oc_calendar_objects

  • oc_calendar_share_calendar

  • oc_calendar_share_event

  • oc_fscache

  • oc_log

  • oc_media_albums

  • oc_media_artists

  • oc_media_sessions

  • oc_media_songs

  • oc_media_users

  • oc_permissions

  • oc_queuedtasks

  • oc_sharing