Datetime functions
- ago
- datetime_add
- datetime_diff
- datetime_part
- dayofmonth
- dayofweek
- dayofyear
- endofday
- endofmonth
- endofweek
- endofyear
- getmonth
- getyear
- hourofday
- monthofyear
- now
- startofday
- startofmonth
- startofweek
- startofyear
- unixtime_microseconds_todatetime
- unixtime_milliseconds_todatetime
- unixtime_nanoseconds_todatetime
- unixtime_seconds_todatetime
- week_of_year