iMac to video display connection

The adapter required between my Mac and a video display I just bought - a mini DVI to DVI adapter - is too short. It couldn't even connect the 2 things if they were back to back.
I looked up the Apple store web site and couldn't find anything longer. How do people do?
Amazon offers a 6-feet long "Mini DisplayPort to DVI Male Adapter Cable". Would this work? (in other words: are Mini DisplayPort and mini DVI the same thing?)
Thank you.

The idea is to use the adapter to further connect to a DVI cable which you can buy from most dealers who sell them. I did that with my older MacBook for years. You don't need a longer adapter, you need a DVI extension cable.

Thank you!