How can error handling techniques like mysql_error be utilized effectively in PHP?

When using error handling techniques like mysql_error in PHP, it is important to check for errors after each MySQL query execution to ensure that the query was successful. By utilizing mysql_error, you can capture any errors that occur during the query execution and handle them appropriately, such as displaying an error message to the user or logging the error for further investigation.

// Perform a MySQL query
$result = mysqli_query($connection, "SELECT * FROM users");

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

// Process the query result
while ($row = mysqli_fetch_assoc($result)) {
    // Do something with the data
}

// Free the result set
mysqli_free_result($result);