Database

Memos supports three database backends:

• sqlite for the default single-instance setup
• mysql for managed or larger deployments
• postgres for managed or larger deployments

SQLite

SQLite is the default and the best fit for most personal deployments or small teams running a single node.

Useful defaults in Memos include WAL mode and a busy timeout, which help reduce common lock contention problems.

Typical SQLite setup:

MEMOS_DRIVER=sqlite MEMOS_DATA=/var/opt/memos memos

If you need an explicit file path:

MEMOS_DRIVER=sqlite MEMOS_DSN=/opt/memos/memos.db memos

SQLite is usually enough when:

• one instance handles all writes
• your dataset is modest
• operational simplicity matters more than cluster-style scaling

MySQL and PostgreSQL

Use MySQL or PostgreSQL when:

• you want managed backups and tooling
• you already operate a database server
• you expect larger datasets or more operational controls
• you do not want the application host to carry the database file locally

Examples:

MEMOS_DRIVER=mysql \
MEMOS_DSN="memos_user:password@tcp(db:3306)/memos?charset=utf8mb4&parseTime=True&loc=Local" \
memos

MEMOS_DRIVER=postgres \
MEMOS_DSN="postgres://memos_user:password@db:5432/memos?sslmode=disable" \
memos

Selection guidance

• choose SQLite for one-node simplicity
• choose MySQL or PostgreSQL for operational flexibility
• keep backups aligned with your database choice
• if you store attachments outside the database, back those up separately

Performance implications

Database choice changes where bottlenecks show up:

• SQLite tends to surface write contention first
• MySQL and PostgreSQL push complexity into networked DB operations and tuning
• attachment storage can dominate recovery and backup time even when the DB is healthy