Databases
MySQL, MariaDB, PostgreSQL, Redis and MongoDB on a VPS.
64 guides · page 2 of 4
Fix MySQL Charset and Collation Mismatches
Find where a MySQL charset or collation mismatch lives — server, database, table, column or connection — and fix it without corrupting your data.
Fix MySQL Socket Error: Can't Connect to Local Server
ERROR 2002 means the MySQL client could not reach the server over its Unix socket. Check the service, find the real socket path, and fix the client config.
Fix MySQL Too Many Connections Errors
Diagnose MySQL error 1040, find which clients are holding connections open, raise max_connections safely and tune wait_timeout to stop the leak coming back.
Fix PostgreSQL "Too Many Clients Already" Errors
Diagnose and fix the PostgreSQL FATAL: sorry, too many clients already error by finding idle backends, tuning max_connections and adding a connection pooler.
Fix PostgreSQL Password Authentication Failed for User
Diagnose and fix the PostgreSQL "password authentication failed for user" error by checking pg_hba.conf rules, resetting the role password and reloading the server.
Fix Redis MISCONF RDB Snapshot Saving Error
The Redis MISCONF error means a background RDB save failed, so Redis stopped accepting writes. This guide finds the cause and restores saving safely.
How to back up and restore MySQL databases with mysqldump
Back up one or all MySQL and MariaDB databases with mysqldump, keep InnoDB dumps consistent, compress them with gzip, and restore them safely with the mysql client.
How to check database and table sizes in MySQL and MariaDB
Find out how much space each MySQL or MariaDB database and table uses, spot the biggest tables, and compare the numbers with real disk use on your VPS.
How to create a database and user for a web app in MySQL or MariaDB
Set up a utf8mb4 database and a dedicated user with a strong password for WordPress, Laravel or any web app, then test the login before you configure the app.
How to create a MySQL user and grant privileges
Create MySQL and MariaDB user accounts, understand the host part, grant only the rights each app needs, and review, revoke or drop access safely.
How to install and secure Redis on a Linux VPS
Install Redis on Ubuntu, Debian, AlmaLinux or Rocky Linux, keep it on localhost, require a password or ACL user, and run it under systemd.
How to install MariaDB on AlmaLinux and Rocky Linux
Install MariaDB on AlmaLinux or Rocky Linux 8 and 9 from AppStream or the official MariaDB repository, secure it, enable the service and handle SELinux.
How to install MongoDB on Ubuntu and secure it
Install MongoDB on Ubuntu from the official repository, enable authentication, create an admin user, and restrict access with bindIp and UFW.
How to install MySQL 8.4 on Ubuntu and Debian
Install MySQL on Ubuntu or Debian from the distribution packages or the official MySQL APT repository, secure it and make your first connection.
Import a Large MySQL SQL File Without Timeouts
Import a large MySQL dump from the command line without phpMyAdmin timeouts. Raise packet limits, split oversized files and verify the result.
Import and export a MySQL database with phpMyAdmin in cPanel
Use phpMyAdmin in cPanel to export a database to an .sql file, import a backup, run queries, and handle large files or upload size errors.
Install Redis and Secure It with a Password
Install Redis on Ubuntu, Debian, AlmaLinux or Rocky Linux, set a password with requirepass, and confirm the server rejects unauthenticated commands.
Install the latest PostgreSQL from the official PGDG repository
Add the PostgreSQL project's own apt or dnf repository to get a current major version on Ubuntu, Debian, AlmaLinux or Rocky Linux, and run more than one version side by side.
Manage MySQL databases and users in cPanel: create, rename, grant and delete
Use cPanel MySQL Databases to create databases and users, assign the right privileges, rename or delete databases safely, and fix common access denied errors.
MySQL command-line cheat sheet for server admins
The MySQL and MariaDB commands you use most on a VPS, from logging in and listing databases to finding slow queries, killing them and checking server status.
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