DateTime related functions are as follows:

Name Description
datediff() difference (signed integer) between the two date-times.
date_format() convert date-time as specified format into CHAR string
day() month day of the date
hour() hour of the date-time
isoweek() iso week number of the date, e.g. 2016-W2
minute() minute of the date-time
month() month of the date
now() current date-time.
quarter() 1-4, quarter of the date
second() second of the date-time
timediff() difference (signed integer) between the two date-times.
timestamp() timestamp of the date-time
time_seg() partition date-time into time segments with the same length of period.
week() week number of the date.
weekday() 0 (Sunday) - 6 (Saturday), week day of the date.
year() year of the date
yearday() 0-365, day number of the year of the date.
yearweek() week number of the date, e.g. 2016-W1

DATEDIFF

datediff(datepart, startdate, enddate)

Function datediff returns the difference specified by the datepart between startdate and enddate. The following lists available datepart types:

datepart
year
quarter
month
week
day
hour
minute
second

DATE_FORMAT

date_format(date-time, format)

Function date_format convert a date-time into a CHAR string based on the specified format.

The following format specifiers may be used in the format string.

specifier Description
%a Abbreviated weekday name (Sun..Sat)
%A Full weekday name (Sunday..Saturday)
%b Abbreviated month name (Jan..Dec)
%B Full month name (January..December)
%C Year divided by 100 (00-99)
%d Day of the month (00-31)
%D MM/DD/YY date (08/23/01)
%e Day of the month (0-31)
%F YYYY-MM-DD date (2016-08-23)
%H Hour in 24h format (00-23)
%I Hour in 12h format (01-12)
%m Month (00-12)
%M Minute (00-59)
%p AM or PM
%S Seconds (00-59)
%T HH:MM:SS (14:55:02)
%Y Year (2017)
%% A % character

TIME_SEG

time_seg(date-time, time_window_length, [reference_time])

Function time_seg converts all date-time within the same time window to the start time of the time window. The length of a time window is indicated by the time window specifier. The start time for each time window is determined by the reference_time as a start time. If reference_time is not given, "1970/01/01 00:00:00" is used as the default reference time.

The length of a time window is described as a number followed by a time winodow specifier as shown below:

time windows specifier Description
h hour
m minute
s second

For example, "2h30m" represents a time window of two hours and 30 minutes