Great God to solve the shutdown

How can we solve _ connect (); & nbsp; // connect to MYSQL database _ select_db (); & nbsp; // select the specified database _ set_names (); & nbsp;
_ Connect (); // connect to the MYSQL database
_ Select_db (); // select the specified database
_ Set_names (); // sets the character set
Error

Fatal error: Call to undefined function _ connect () in D: \ wamp \ www \ bbb \ des \ common. inc. php on line 45
Solution
Can you have a group? I am a newbie and have unlimited questions. I will share with you:
------ Solution --------------------
Require ROOT_PATH. 'Des/global. func. php ';
Require ROOT_PATH. 'Des/mysql. func. php ';

The codes of these two files are also posted.
------ Solution --------------------
The problem should be found in define ('root _ path', substr (dirname (_ FILE _), 0,-8 ));
You
Echo ROOT_PATH ,'
';
Echo _ FILE __,'
';
Post result