Update section on MySQL/MariaDB bacup

[theking2]

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Update Backup — Nextcloud section on MySQL/MariaDB

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Notes

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The official MariaDB documents suggest using mariadb-dump to create backups of a MariaDB database.

To backup MariaDB

mariadb-dump --user=[dbuser] --password=[dbpassword] [dbname] > nextcloud-sqlbkp_`date +"%Y%m%d"`.bkp

or compress if the database is large

mariadb-dump --user=[dbuser] --password=[dbpassword] [dbname] | gzip > nextcloud-sqlbkp_`date +"%Y%m%d"`.bkp.gz

To restore MariaDB

mariadb --user=[dbuser] --password=[dbpassword] < nextcloud_sqlbkp_.bkp

or if compressed

gunzip nextcloud_sqlbkp.bkp.gz | mariadb --user=[dbuser] --password=[dbpassword]