根据你安装的驱动，有如下两种连接字符串形式。
Provider=DB2OLEDB;Network Transport Library=TCPIP;Network Address=xxx.xxx.xxx.xxx;Initial Catalog=MyCtlg;Package Collection=MyPkgCol;Default Schema=Schema;UserID=myUsername;Password=myPassword;

Provider=IBMDADB2;Database=myDataBase;Hostname=myServerAddress;Protocol=TCPIP; Port=50000;Uid=myUsername;Pwd=myPassword;

DB2 VC++ 中连接字符串