weird, we had just recently a (long, tortured, and semi-hijacked) thread with exactly the same premise...
my advice to you is the same as i gave early in that thread (post #12) --
all you need for your query is a simple SELECT, one that returns the rows you want in timestamp order
then, in your php code (if php is what you're using), look at each returned row and compare it to the previous row, and when the day changes, print the new day as a header before printing that result row
if i did php, i'd mock up the code for you, but i don't (i do coldfusion instead)
"current/previous" logic is actually fairly common, and as far as detecting a date change, i'm sure php has the appropriate functions
p.s. note that i put
date in backticks, because DATE is a reserved word in mysql... you'd be better off renaming that column