COQL - DATE() function doesn't seam to work...

COQL - DATE() function doesn't seam to work...

Hi,

I'm trying to get the DATE part from a DATETIME and I always get "unsupported aggregate function", is there another function to do it?
How can we do a SELECT with an GROUP BY on a DATETIME if you can't use DATE to group by DATE and not the full datetime that would be ridiculous.

Thank you!