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- $isoDayOfWeek (aggregation)
$isoDayOfWeek (aggregation)¶
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Definition¶
-
$isoDayOfWeek
¶ New in version 3.4.
Returns the weekday number in ISO 8601 format, ranging from
1
(for Monday) to7
(for Sunday).$isoDayOfWeek
has the following operator expression syntax:The argument can be any valid expression that resolves to a BSON ISODate object, a BSON Timestamp object, or a Date object.
Behavior¶
Example | Result |
---|---|
{ $isoDayOfWeek: new Date("2016-01-01") } |
5 |
{ $isoDayOfWeek: new Date("Jan 7, 2003") } |
2 |
{ $isoDayOfWeek: new Date("August 14, 2011") } |
7 |
{ $isoDayOfWeek: ISODate("1998-11-07T00:00:00Z") } |
6 |
{ $isoDayOfWeek: "March 28, 1976" } |
error |
{ $isoDayOfWeek: "2009-04-09" } |
error |
Note
$isoDayOfWeek
cannot take a string as an argument.
Example¶
A collection called birthdays
contains the following documents:
The following operation returns the weekday number for each
birthday
field.
The operation returns the following results: