It doesn't look like you're using the value of $i in either of your loops, instead some arbitrary variables that were set elsewhere. If this is your real query then you don't need a loop at all, in fact your select statement would return the same row every time if you actually fetched from it. If you're trying to get 800 results then use one query with LIMIT

If this is just an example then I think we need more info on what you're trying to accomplish.