Warning Displaying Image in Perl

I have a graphic.cgi file which gives an output of image. I have one more file with name design.cgi where i am using graphic.cgi in the html code i.e,

print <<hello
<img src="graphic.cgi?database login stuff" alt=" something"/>


Image is displaying on the html page but i am getting an warning saying use of uninitialized value at print statement which is print <<hello.
please help. should i add anything else to resolve this issue . and both the files graphic.cgi and design.cgi contains mysql code aswell.