Warning: Undefined variable $tid in C:\wwwroot\hvc.cc\lefter.php on line 14

PHPMyWind安全警告：MySql Error！

错误文件：/contact.php
错误信息：You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') ORDER BY orderid DESC' at line 1 Error sql: SELECT * FROM `pmw_infoclass` WHERE (id=) ORDER BY orderid DESC

Fatal error: Uncaught TypeError: mysqli_num_rows(): Argument #1 ($result) must be of type mysqli_result, bool given in C:\wwwroot\hvc.cc\include\mysqli.class.php:395 Stack trace: #0 C:\wwwroot\hvc.cc\include\mysqli.class.php(395): mysqli_num_rows(false) #1 C:\wwwroot\hvc.cc\include\page.class.php(48): MySql->GetTotalRow() #2 C:\wwwroot\hvc.cc\lefter.php(14): Page->GetPage('SELECT * FROM `...', 1) #3 C:\wwwroot\hvc.cc\contact.php(38): require_once('C:\\wwwroot\\hvc....') #4 {main} thrown in C:\wwwroot\hvc.cc\include\mysqli.class.php on line 395