How PHP mysqli_rollback function works?

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In PHP, the mysqli_rollback function is used to roll back the current transaction for the specified database connection. It is commonly used in database applications to undo changes made during the current transaction, reverting the database to its previous state before the transaction began.

Here's how you use the mysqli_rollback function:

php code

mysqli_rollback($connection);

In this syntax:

mysqli_rollback is the PHP function used for rolling back a transaction.

$connection is the variable representing the MySQL database connection object created using the mysqli_connect function.

When you call mysqli_rollback($connection), it discards all the changes made during the current transaction and ends the transaction. It is essential to note that this function should be used in conjunction with the mysqli_begin_transaction function, which starts a new transaction.

Here's an example of how you might use mysqli_rollback in a transaction:

php code

// Create a new database connection

$connection = mysqli_connect("localhost", "username", "password", "database");

// Check connection

if (!$connection) {

    die("Connection failed: " . mysqli_connect_error());

}

// Start a new transaction

mysqli_begin_transaction($connection);

// Perform some database operations

mysqli_query($connection, "UPDATE table_name SET column_name = 'new_value' WHERE condition");

// Check if the update was successful

if ($update_successful) {

    // Commit the transaction

    mysqli_commit($connection);

} else {

    // Roll back the transaction if the update fails

    mysqli_rollback($connection);

}

// Close the database connection

mysqli_close($connection);

In this example, if the update operation is successful, the changes are committed to the database using mysqli_commit. If the update operation fails for any reason, the mysqli_rollback function is called to discard the changes made during the transaction, ensuring the database remains in a consistent state.

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