


Why am I getting an \'Unknown Database Error\' with PDO when my database exists in phpMyAdmin?
Nov 04, 2024 am 06:19 AMTroubleshooting "Unknown Database Error" with PDO when Database Exists in PHPMyAdmin
When attempting to establish a connection to a MySQL database using PDO, you may encounter an "Unknown database error" despite the presence of the database in PHPMyAdmin. This issue is typically attributed to two root causes:
1. Spelling Error
Verify the spelling of the database name to ensure it matches precisely with the one created in PHPMyAdmin. Even minor discrepancies can trigger a connection failure.
2. Server Disparity
PHPMyAdmin and your PHP code may be connecting to different database servers. To confirm this, you can execute the following query in both PHPMyAdmin and PHP:
A comparison of the output from both sources will reveal any potential disparities.
If the database name and server configuration are correct, you may encounter additional issues. Check the following:
- Database Privileges: Ensure that the database user you are connecting with has the necessary privileges to access the newly created database.
- MySQL Version: PDO may not be able to connect to older versions of MySQL. Verify that you are using a compatible version.
- PHP Extensions: Make sure the PDO and MySQL extensions are properly installed and enabled in your PHP configuration.
- Firewall Settings: Check if any firewall settings are blocking the connection between PHP and the database server.
If you have ruled out all of the above, consider the possibility of a bug or compatibility issue with your PHP code. Debug the code carefully to isolate the source of the error.
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