Fatal error: Uncaught TypeError: mysqli_num_rows(): Argument #1 ($result) must be of type mysqli_result, bool given in /home/sandelz/public_html/graph_app/test.php:25
Stack trace:
#0 /home/sandelz/public_html/graph_app/test.php(25): mysqli_num_rows(false)
#1 {main}
thrown in /home/sandelz/public_html/graph_app/test.php on line 25