


Why is my PHP script throwing 'mysqli::query(): MySQL Object Already Closed or Unable to Fetch MySQL Error'?
Dec 16, 2024 pm 10:18 PMmysqli::query(): MySQL Object Already Closed or Unable to Fetch MySQL Error
Problem
While executing a PHP script, you encounter the following errors:
- PHP 7: mysqli::query(): Couldn't fetch MySQL in [script_path] on line [line_number]
- PHP 8: Uncaught Error: MySQL object is already closed
Explanation
These errors indicate that your PHP script is attempting to perform a MySQL query after the MySQL connection object has been closed.
Solution
Ensure that your MySQL connection object is still active before executing any queries.
// Check if the MySQL connection is open if ($mysqli->connect_error) { // Handle the connection error } else { // Execute the query $result = $mysqli->query($query); }
Possible Causes
- Closing the connection too early: Ensure that you close the MySQL connection only after all queries have been executed.
- Destructor issues: Avoid closing the MySQL connection in the destructor (__destruct) method of a class if there are still queries that need to be performed.
- Incorrectly declared connection variables: Check that the MySQL connection variable ($mysqli in this case) is declared and assigned correctly throughout your script.
Additional Notes
- In the provided code snippet for the class EventCalendar, the MySQL connection is closed in the destructor (__destruct) method. This could be an issue if queries are still needed after the destructor is called.
- Ensure that you are using the correct PHP version and MySQL extension.
- Check the MySQL server logs for any additional error messages.
The above is the detailed content of Why is my PHP script throwing 'mysqli::query(): MySQL Object Already Closed or Unable to Fetch MySQL Error'?. For more information, please follow other related articles on the PHP Chinese website!

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