Date Operators

Operator	Description	Example
$dayOfWeek	Returns the day of the week for the passed in date property or expression as a number from 1 (Sunday) to 7 (Saturday).	{"$dayOfWeek": "created"}
$dayOfMonth	Returns the day of the month for the passed in date property or expression as a number from 1 to 31	{"$dayOfMonth": "created"}
$dayOfYear	Returns the day of the year for the passed in date property or expression as a number from 1 to 366	{"$dayOfYear": "created"}
$year	Returns the year for the passed in date property or expression.	{"$year": "created"}
$month	Returns the month for the passed in date property or expression.	{"$month": "created"}
$week	Returns the week of the year for the passed in date property or expression as a number between 0 (the partial week that precedes the first Sunday of the year) and 53 (in a leap year).	{"$week": "created"}
$hour	Returns the hour for the passed in date property or expression as a number between 0 and 23.	{"$hour": "created"}
$minute	Returns the minute for the passed in date property or expression as a number between 0 and 59.	{"$minute": "created"}
$second	Returns the second for the passed in date property or expression as a number between 0 and 60 (for a leap second).	{"$second": "created"}
$millisecond	Returns the millisecond for the passed in date property or expression as a number between 0 and 999.	{"$millisecond": "created"}
$dateToString	Converts a date object to a string in a specified format, and expects an array of [<format>, date_expression][<format>, date_expression]	{ "$dateToString": ["%Y-%m-%d", "created"] }

Date Format Specifiers

Specifiers	Description	Possible Values
%d	Day of Month (2 digits, zero padded)	01-31
%G	Year in ISO 8601 format	0000-9999
%H	Hour (2 digits, zero padded, 24-hour clock)	00-23
%j	Day of year (3 digits, zero padded)	001-366
%L	Millisecond (3 digits, zero padded)	000-999
%m	Month (2 digits, zero padded)	01-12
%M	Minute (2 digits, zero padded)	00-59
%S	Second (2 digits, zero padded)	00-60
%u	Day of week number in ISO 8601 format (1-Monday, 7-Sunday)	1-7
%U	Week of year (2 digits, zero padded)	00-53
%V	Week of Year in ISO 8601 format	1-53
%w	Day of week (1-Sunday, 7-Saturday)	1-7
%Y	Year (4 digits, zero padded)	0000-9999
%%	Percent Character as a Literal	%