What causes the \"#126 - Incorrect key file for table\" error in MySQL and how can I fix it?

MySQL: Addressing the "#126 - Incorrect Key File for Table" Error

When attempting to execute a MySQL query, users may encounter the cryptic error "#126 - Incorrect key file for table." This perplexing error can arise even without the presence of explicitly declared keys or indices.

Problem Exploration:

Typically, this error occurs when a table is altered with a full disk condition. However, recent updates have identified another potential trigger: a full ramdisk during resource-intensive operations like table alterations.

Solution Approaches:

1. Disk Utilization Evaluation:

• Verify the available disk space on the server hosting the MySQL database. Insufficient disk space can hinder table operations and trigger the "#126" error message.
• If the disk is at or near capacity, consider clearing unnecessary files or expanding the storage space.

2. Ramdisk Management (if applicable):

• Check if the system utilizes a ramdisk for caching purposes.
• If a ramdisk is enabled, temporarily remove the configuration line to alleviate the full ramdisk condition.
• Alter the table as needed, then re-enable the ramdisk once the operation is complete.

Additional Considerations:

If neither of these approaches resolves the issue, further investigation may be necessary. Consider the following:

• Confirm that the user account attempting to execute the query has the necessary privileges.
• Check for potential file corruption by running the 'CHECK TABLE' command on the affected table.
• Monitor system logs for additional error messages that can provide more context.

The above is the detailed content of What causes the \"#126 - Incorrect key file for table\" error in MySQL and how can I fix it?. For more information, please follow other related articles on the PHP Chinese website!