What role does the mysql_error() function play in troubleshooting SQL queries in PHP?

The mysql_error() function in PHP is used to retrieve the error message from the most recent MySQL operation. This can be helpful in troubleshooting SQL queries as it provides information about any errors that occurred during the execution of the query. By checking the error message returned by mysql_error(), developers can identify and address issues in their SQL queries more effectively.

// Execute SQL query
$result = mysql_query($query);

// Check for errors
if (!$result) {
    echo "Error: " . mysql_error();
} else {
    // Process query results
}