Can I use gtk to design a complex program?

[beyond_2000 <beyond_2000 21cn com>]

Hi,everybody
   I'm a newbie, this is my first learning programming in gtk. Is it as 
powerful as QT or Kylix and so on? I want to program a financial system 
for my company with MySQL database background. Does gtk support MySQL well?
   I know there are a lot of large management system such as ERP which 
is programed by VB,VC,DELPHI under Microsoft Windows. But how can we do 
this under linux? So I am puzzled about this. Which is the best tools 
for program a financial system with MySQL or Oracle database background.
   Could you master-hand recommend a c/c++ tools for me to start the work?
   Thanks at advance!