Database backends

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Minetest supports several database backends. This page provides a comparison of all backends.

There are four database backends in Minetest (since 5.6.0):

• Map
• Players
• Authentication
• Mod Storage

Map backend

The database backend is set using the backend setting in world.mt. Put the name of the backend in lowercase as the value of the setting (e.g. backend=sqlite3 for SQLite3).

If you want to migrate a world map to a new backend, use minetestserver --migrate <name of new backend> --world <path to your world directory>. It will automatically update world.mt to reflect the new backend.

If using a client build, server instructions can be given using "minetest --server", e.g. minetest --server --migrate <name of new backend> --world <path to your world directory>.

Player backend

The database backend is set using the player_backend setting in world.mt. If it doesn't exist, the default is files.

If you want to migrate players to a new backend, use minetestserver --migrate-players <name of new backend> --world <path to your world directory>. It will automatically update world.mt to reflect the new backend.

Authentication backend

The database backend is set using the auth_backend setting in world.mt. If it doesn't exist, the default is files.

If you want to migrate the authentication data to a new backend, use minetestserver --migrate-auth <name of new backend> --world <path to your world directory>. It will automatically update world.mt to reflect the new backend.

Mod Storage backend

The database backend is set using the mod_storage_backend setting in world.mt. If it doesn't exist, the default is files.

If you want to migrate mod storage to a new backend, use minetestserver --migrate-mod-storage <name of new backend> --world <path to your world directory>. It will automatically update world.mt to reflect the new backend.

Comparison table

Backend	Speed	Reliability	Compatibility with builds	Map	Players	Authentication	Mod Storage
SQLite3	Good	Acceptable (problems can arise with concurrent accesses)	Very good (always supported)	✔	✔	✔	✔
LevelDB	Good	Good	Mostly supported	✔	✔	✔
Redis	Very good (data kept in RAM)	Good	Inconvenient (Redis server required)	✔
PostgreSQL	Very good (most used data are in memory, others from disk)	Very good	Inconvenient (PostgreSQL server required)	✔	✔	✔	✔ (5.7.0+)
Dummy	Blazing fast	N/A (nothing is saved to disk)	None (nothing is saved to disk)	✔	✔
Files (deprecated)	Bad	Bad	Deprecated (support may be removed)		✔	✔	✔

The Compatibility with builds column is only relevant if you want to distribute the worlds.

SQLite3

SQLite3 is the default backend for all Minetest worlds, it is supported by every Minetest build and is therefore the standard database format that is used to distribute worlds.

LevelDB

LevelDB is mostly used on servers because of its improved reliability and possibly speed. You need to install it additionally.

Redis

Redis support was added to Minetest in April 2014, Redis is mainly useful for servers as it allows multiple worlds to be stored in one Redis instance. You need to install it additionally (libhiredis library).

Information about setting up a Redis server can be found here: https://redis.io/topics/quickstart

world.mt settings for Redis

redis_address -- The IP or hostname of the redis server.

redis_port -- The port of the redis server. Optional, default: 6379

redis_hash -- Hash where the MapBlocks are stored in, if you want multiple worlds in one redis instance this needs to be different for each world. If you don't need that you can use e.g. IGNORED.

PostgreSQL

PostgreSQL support was added to Minetest in May 2016, it's mainly useful for servers as it allows multiple worlds in a single instance, in multiple databases.

PostgreSQL is an excellent alternative to Redis. It doesn't store all data in memory, only recent and frequent data is loaded into memory. All data is on disk storage and data storage is very robust. You can also easily interface a website in front of your database to offer a frontend to your users.

While we support older versions, it is recommended to use PostgreSQL 9.5 at least.

To improve PostgreSQL's performance with Minetest servers, please configure postgresql.conf with a minimum shared_buffer of 512MB, with a maximum of 50% of your server's available RAM.

world.mt for PostgreSQL

pgsql_connection -- PostgreSQL connection string for world map | host=<db_host> user=<db_user> password=<db_password> dbname=<db_name>

pgsql_player_connection -- PostgreSQL connection string for players | host=<db_host> user=<db_user> password=<db_password> dbname=<db_name>

Dummy

A dummy database backend, which stores all MapBlocks in RAM without saving them. This means, as soon the server shuts down or you leave in singleplayer, all changes made to the world are lost. When you re-join, the world will be re-generated from scratch.

This backend is not widely used, but is used by servers which don't need a persistent map — for example, Capture the Flag.

Files

A legacy backend for player and authentification data. Everything is stored in plaintext files. It's slow, unreliable and clunky. Use of this backend is discouraged now and it's possible this backend will be removed in the future.

For mod storage, Files uses the legacy JSON-based storage method as opposed to a regular database system. It is slower and will keep the entire mod storage data in memory.