How can PHP developers ensure proper data integrity when inserting and retrieving timestamps from a MySQL database?

When inserting timestamps into a MySQL database using PHP, developers should ensure that the timestamps are formatted correctly to avoid data integrity issues. This can be achieved by using PHP's `date()` function to format timestamps in the desired format before inserting them into the database. When retrieving timestamps from the database, developers should use PHP's `strtotime()` function to convert the timestamps back into a Unix timestamp format for processing.

// Inserting timestamp into MySQL database
$timestamp = date('Y-m-d H:i:s');
$query = "INSERT INTO table_name (timestamp_column) VALUES ('$timestamp')";
// Execute query

// Retrieving timestamp from MySQL database
$query = "SELECT timestamp_column FROM table_name";
$result = mysqli_query($connection, $query);
$row = mysqli_fetch_assoc($result);
$timestamp = strtotime($row['timestamp_column']);