📋

Description

This error indicates that MySQL cannot locate or connect to an external data source that is being referenced, typically within a FEDERATED table. It occurs when the `CREATE SERVER` definition for the foreign server is incorrect, missing, or inaccessible to the MySQL instance.

💬

Error Message

The foreign data source you are trying to reference does not exist. Data source error: %s

🔍

Known Causes

3 known causes

⚠️

Missing or Invalid Server Definition

The `CREATE SERVER` statement for the foreign data source was never executed, was dropped, or contains incorrect connection parameters for the remote server.

⚠️

Remote Host Unreachable

The MySQL server cannot establish a network connection to the specified remote host due to network issues, incorrect IP address/hostname, or firewall restrictions.

⚠️

Authentication Failure

The username or password specified in the `CREATE SERVER` definition is incorrect or lacks necessary privileges on the remote database server.

🛠️

Solutions

3 solutions available

1. Verify Foreign Data Wrapper (FDW) Installation and Configuration medium

Ensure the necessary FDW plugin is installed, enabled, and correctly configured for the foreign server.

1

Identify the foreign data wrapper being used. This is usually specified when creating the `FOREIGN SERVER` object.

SELECT * FROM information_schema.foreign_data_wrappers;

2

Check if the identified foreign data wrapper is installed and available on your MySQL server. The exact method depends on the FDW, but often involves checking plugin directories or system logs.

SHOW PLUGINS;

3

If the FDW is not installed, you will need to install it according to its specific documentation. This might involve compiling from source or installing a pre-compiled package.

Example (conceptual, actual command varies by FDW):
INSTALL PLUGIN my_fdw SONAME 'my_fdw.so';

4

Verify the `FOREIGN SERVER` definition. Ensure that the `FOREIGN DATA WRAPPER` clause correctly points to the installed FDW.

SHOW CREATE SERVER your_foreign_server_name;

5

Review the configuration options for the foreign server. Some FDWs require specific options to be set during `CREATE SERVER` or `ALTER SERVER`.

SHOW CREATE SERVER your_foreign_server_name;

2. Correct Foreign Server Name and Connection Details easy

Double-check that the foreign server name used in your query or table definition exactly matches the name of the registered foreign server.

1

List all defined foreign servers to see the exact names and their associated FDWs.

SELECT * FROM information_schema.foreign_servers;

2

Examine the `FOREIGN TABLE` definition or the query that is failing. Ensure the `SERVER` clause (or equivalent) uses the precise name from the `information_schema.foreign_servers` table.

Example `FOREIGN TABLE` definition:
CREATE FOREIGN TABLE my_remote_table (
    id INT,
    name VARCHAR(255)
)
SERVER my_remote_server_name
OPTIONS (table_name 'remote_table');

3

If the name is incorrect, drop and recreate the `FOREIGN TABLE` or `FOREIGN SERVER` with the correct name, or use `ALTER SERVER` if supported by the FDW for renaming.

DROP FOREIGN TABLE IF EXISTS my_remote_table;
-- Recreate with correct server name
CREATE FOREIGN TABLE my_remote_table (
    id INT,
    name VARCHAR(255)
)
SERVER correct_remote_server_name
OPTIONS (table_name 'remote_table');

3. Restart MySQL Service After FDW Installation/Update easy

In some cases, changes to FDW plugins or configurations require a MySQL service restart to take effect.

1

After installing or updating a foreign data wrapper plugin, it's often necessary to restart the MySQL server for the changes to be recognized.

For systemd-based systems (most modern Linux):
sudo systemctl restart mysql

For older init.d systems:
sudo service mysql restart

For Windows:
Open Services (services.msc), find the MySQL service, and restart it.

2

After the service restarts, try executing your query or accessing the foreign table again.

SELECT * FROM my_remote_table LIMIT 10;

🔗

Related Errors

5 related errors

MySQL Error 1431: Foreign Data Source Missing