How to Troubleshoot the \'Got a packet bigger than \'max_allowed_packet\' bytes\' Error in MySQL?

How to Verify and Adjust 'max_allowed_packet' Variable in MySQL

Background

The MySQL 'max_allowed_packet' variable sets the maximum size of data packets that can be transmitted during a database operation. An error may occur if a packet exceeds this limit, displaying the message "[1153] Got a packet bigger than 'max_allowed_packet' bytes."

Checking 'max_allowed_packet'

To determine the current value of 'max_allowed_packet':

$mysqli = new mysqli('host', 'username', 'password', 'database');
$stmt = $mysqli->prepare("SHOW VARIABLES LIKE 'max_allowed_packet'");
$stmt->execute();
$stmt->bind_result($var_name, $var_value);
$stmt->fetch();
$stmt->close();

echo "Current max_allowed_packet: $var_value";

Adjusting 'max_allowed_packet'

It is important to note that 'max_allowed_packet' is configured in MySQL's configuration file, not within PHP code. This variable can be found in the '[mysqld]' section of the MySQL configuration file typically located at '/etc/my.cnf' or '/var/lib/mysql/my.cnf'.

To adjust this value:

1. Locate the '[mysqld]' section in the configuration file.
2. Add or modify the line: max_allowed_packet=16M (increase the value as needed).
3. Save and close the configuration file.
4. Restart the MySQL service to apply the changes.

Note:

On shared hosting environments, changing 'max_allowed_packet' may not be allowed or require administrator intervention. It is recommended to contact your hosting provider if you need to adjust this setting.

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