How can PHP error messages such as "supplied argument is not a valid MySQL result resource" be troubleshooted and resolved when querying data from a MySQL database?

The error message "supplied argument is not a valid MySQL result resource" typically occurs when the query execution fails or returns an error. To troubleshoot and resolve this issue, you should check the query syntax, database connection, and handle potential errors properly. Make sure that the query is executed successfully and the result is a valid MySQL result resource before trying to fetch data from it.

// Example PHP code snippet to troubleshoot and resolve "supplied argument is not a valid MySQL result resource" error
$query = "SELECT * FROM table_name";
$result = mysqli_query($connection, $query);

if (!$result) {
    die("Error: " . mysqli_error($connection));
}

// Proceed with fetching data from the result
while ($row = mysqli_fetch_assoc($result)) {
    // Process data here
}