Storing date & time individually did originally seem like a better idea,
as it allowed nice indexing of the days which makes for faster lookups,
however, since standalone day & time informations don't carry timezone
data, doing this is problematic.
One option would be to introduce another field for the timezone, but
this just seems to be needlessly to complex, instead, store the start &
end event times as full datetimes. These will still be indexed and
should still result in sufficiently fast lookups.
Additionally, this also adds a compound index for start time & end time,
to improve speeds when searching by both at once.
Peter Vacho