MySQL SHOW ERRORS Statements

The `SHOW ERRORS` statement in MySQL is used to display error messages generated by the most recent SQL statement execution within the current session. It provides insights into what went wrong, helping users diagnose and fix issues in their queries. It is part of MySQL's diagnostic tools intended for error reporting. Unlike `SHOW WARNINGS`, which displays warning and note messages, `SHOW ERRORS` specifically focuses on error messages.

Usage

`SHOW ERRORS` is typically used after executing a SQL statement that fails, to obtain detailed information about the error. It is especially useful for debugging purposes and ensuring query correctness.

SHOW ERRORS
[LIMIT [offset,] row_count];

In this syntax, `SHOW ERRORS` retrieves error messages, and you can limit the number of errors displayed with the optional `LIMIT` clause.

Examples

1. Basic Error Display

SHOW ERRORS;

This command retrieves all error messages from the most recent SQL statement, displaying up to the maximum number allowed by the server.

2. Limiting Error Output

SHOW ERRORS LIMIT 5;

This example limits the display to the first 5 error messages, useful for focusing on the most critical issues when there are numerous errors.

3. Offset and Limit

SHOW ERRORS LIMIT 2, 3;

This usage skips the first 2 error messages and then displays the next 3, allowing users to page through errors efficiently.

Tips and Best Practices

• Immediate Use: Run `SHOW ERRORS` immediately after a query returns an error to capture relevant details.
• Error and Warning Context: For a comprehensive view of issues, use `SHOW ERRORS` in conjunction with `SHOW WARNINGS`.
• Manageable Output: Use the `LIMIT` clause to manage output size, focusing on specific errors.
• Understanding Error Codes: Pay attention to error codes for deeper insights and more targeted troubleshooting. Error codes can often be cross-referenced with MySQL documentation for detailed explanations and solutions.

Consider checking the compatibility of `SHOW ERRORS` across different MySQL versions, as features may vary.