SQLite is good for testing and simple single-user Nextcloud instance,
but it does not scale for multiple-user production cases. For the first Installation its quiet simple and reliable.
After some years of usage my SQLite-database reached a size of 130MB and the performance was not more the same as after the first days.
You can convert a SQLite database to a more performing MariaDB database with the Nextcloud command line tool:
sudo -u www-data php occ db:convert-type --all-apps mysql db_username dbserver.example.com nextcloud_db
Before you go on with the command,
create a databases user with database-specific permissions to increase the usage to the nextlocud database.
If you are using a database replication you have to change the binlog format in your mysql-configuration – my.cnf.
binlog_format = MIXED