How can developers troubleshoot issues with empty arrays when values are being retrieved from a database in PHP?

When developers encounter issues with empty arrays when retrieving values from a database in PHP, they should first check the database query to ensure it is correctly fetching the data. They should also verify that the database connection is established and working properly. If the query is correct and the connection is established, developers can use functions like `mysqli_num_rows` to check if any rows are returned from the query before attempting to retrieve values from the array.

// Assuming $conn is the database connection object

$query = "SELECT * FROM table_name";
$result = mysqli_query($conn, $query);

if(mysqli_num_rows($result) > 0) {
    $data = mysqli_fetch_all($result, MYSQLI_ASSOC);
    // Process the retrieved data
} else {
    echo "No data found in the database.";
}