for learning purposes, why does php cries about the following code and gives the following warning:
Warning: mysqli_stmt::close() [mysqli-stmt.close]: invalid object or resource mysqli_stmt in C:\public_html\admin\disctrack.php on line 14
12 $conn = connect('w'); // connect to a database in write mode
13 $stmt = $conn->stmt_init(); // initialize a prepared statement
14 $stmt->close(); // close statement