Deck addition help

I am getting confused after talking to several people about how to add on to my deck to incorporate our pool. The current deck butts up to the pool on the side, deck floor is 20" from the pool top rail. I want to add on/ or new deck for pool level access.
the addition would be 12X22, and I would add stairs from the existing to the new.
The new deck height will be 50", I plan to 4x4 around the outside every 6', 2x8X12 joist and hangers, 5/4X6 db all treated pine.
the end sections are the 12' and the middle is 7 1/2', I made a very rough drawing and attached as a word doc.

the question is the sections that the joist will run the full 12' which at one end is 7' and the other end 6' do I need to install a small beam at both ends?

one guy says yes, and another said no, and the last one said no beam, double band and use 2x10's

Any replies would be greatly appreciated