Once glued up the top will essentially move as one large piece so as with any piece of furniture accommodation for movement needs to be where the top is joined to the base. It might be worthwhile to do some research and pick a wood that has a low(er) expansion coefficient to minimize movement.

Mike is correct. This is basic woodworking 101. Wide board table tops WILL move and moreso with humidity and temperature fluctuations. If you don't build to allow movement, the table will crack down the middle. Also, you need to control board warpage (Battens / Breadboard ends) and use kiln dried lumber, not what you buy at Home Depot. This may be a bigger project than you anticipate. Good luck.

Duane Collie