Deck: post-to-joist attachement

I am planning on building a floating deck in the near future using precast cement piles. I plan on putting a treated 4x4 post vertically into the pile. Now this is where my question is....Do I attache the horizontal joists to the side of the 4x4 post using appropriate bolts or do I place the joists on top of the post? The reason I would like to attache the joists to the sides of the vertical 4x4 posts is so that I do not need to go through the hassle of making sure all my piles are are the same level. If I place the joists on top of the 4x4 post how does one secure it to the post. I am probably going to use 2x6's as my joists. The deck height is very minimal...(ie: ~1ft). Ideas??? Suggestions??? :wink: