How can developers effectively debug PHP code to identify issues like only the first result being displayed?

To identify issues like only the first result being displayed in PHP code, developers can start by checking the loop structure used to display the results. They should ensure that the loop is correctly iterating through all the results and not stopping after the first one. Additionally, they can use debugging tools like var_dump() or print_r() to inspect the data being retrieved from the database and verify that all the results are being fetched.

// Example code snippet to fix the issue of only the first result being displayed
$results = // code to fetch results from the database

// Check if results are fetched successfully
if ($results) {
    foreach ($results as $result) {
        // Display each result here
        echo $result['column_name'] . '<br>';
    }
} else {
    echo 'No results found';
}