1049ERRORTier 1 — Safe✅ HIGH confidence

Unknown database

Category: SchemaVersions: All MariaDB / MySQL versions

What this means

Error 1049 (SQLSTATE 42000) is returned when a USE statement or a connection string specifies a database that does not exist on the server. It is one of the most common connection-time errors in application deployment.

Why it happens

1The database was not created before the application started
2The database name in the connection string has a typo
3The database was created on a different server or environment
4The database was accidentally dropped

How to reproduce

A USE statement references a database that does not exist.

trigger — this will ERROR

USE myapp_production;

ERROR 1049 (42000): Unknown database 'myapp_production'

Fix 1: Create the database

When the database should exist but was never created.

fix

CREATE DATABASE IF NOT EXISTS myapp_production
  CHARACTER SET utf8mb4
  COLLATE utf8mb4_unicode_ci;

Why this works

CREATE DATABASE creates the schema directory and registers the database in information_schema. IF NOT EXISTS prevents an error if it was already created by another process.

Fix 2: List existing databases to find the correct name

When the database exists but the name may be wrong.

fix

SHOW DATABASES;

Why this works

SHOW DATABASES lists all databases the current user has access to, allowing the correct name to be confirmed.

What not to do

✗

Create an empty database in production without running migrations

Why it's wrong: An empty database will cause further errors when the application attempts to query non-existent tables. Always run schema migrations after creating the database.

Version notes

All versionsMariaDB database names are case-sensitive on case-sensitive filesystems (Linux) and case-insensitive on case-insensitive filesystems (Windows, macOS).

Sources

📚 Official docs: https://mariadb.com/kb/en/create-database/

🔧 Source ref: MariaDB Server error code 1049 / ER_BAD_DB_ERROR

📖 Further reading: MariaDB CREATE DATABASE

Confidence assessment

✅ HIGH confidence

Stable.