This mysqlconnection is already in use

MySQLConnection Already in Use Error

The “MySQLConnection already in use” error occurs when you try to establish a new database connection while an existing connection is still active. This limitation is imposed by MySQL server and can be encountered in various scenarios, such as:

• Opening multiple connections within a single script/application
• Trying to reuse an active connection before closing it
• Attempting to connect to the same database concurrently from different scripts/processes

To prevent this error, you should ensure that there is only one active connection at a time or properly manage and close connections before opening new ones.

Here are a couple of examples to demonstrate how to handle this error:

// Example 1: Closing the existing connection before opening a new one

// Close the existing connection
$conn->close();

// Open a new connection
$mysqli = new mysqli($hostname, $username, $password, $database);

if($mysqli->connect_errno) {
    echo "Failed to connect to MySQL: " . $mysqli->connect_error;
    exit();
}

// Perform database operations with the new connection

// Example 2: Checking if a connection is already active before establishing a new one

if(!$mysqli->ping()) {
    // Open a new connection if no active connection present
    $mysqli = new mysqli($hostname, $username, $password, $database);

    if($mysqli->connect_errno) {
        echo "Failed to connect to MySQL: " . $mysqli->connect_error;
        exit();
    }
}

// Perform database operations with the connection

By properly managing your connections and ensuring only one active connection at a time, you can avoid the “MySQLConnection already in use” error in your MySQL database applications.