翻译或纠错本页面
- Reference >
- Operators >
- Aggregation Pipeline Operators >
- Date Aggregation Operators >
- $isoWeek (aggregation)
$isoWeek (aggregation)¶
On this page
Definition¶
- $isoWeek¶
3.4 新版功能.
Returns the week number in ISO 8601 format, ranging from 1 to 53. Week numbers start at 1 with the week (Monday through Sunday) that contains the year’s first Thursday.
$isoWeek has the following operator expression syntax:
{ $isoWeek: <date expression> }
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 |
---|---|
{ $isoWeek: new Date("2016-01-01") } | 53 |
{ $isoWeek: new Date("2015-01-01") } | 1 |
{ $isoWeek: new Date("August 14, 2011") } | 32 |
{ $isoWeek: ISODate("1998-11-07T00:00:00Z") } | 45 |
{ $isoWeek: "March 28, 1976" } | error |
{ $isoWeek: "2009-04-09" } | error |
注解
$isoWeek cannot take a string as an argument.
Example¶
A collection called deliveries contains the following documents:
{ "_id" : 1, "date" : ISODate("2006-10-24T00:00:00Z"), "city" : "Boston" }
{ "_id" : 2, "date" : ISODate("2011-08-18T00:00:00Z"), "city" : "Detroit" }
The following operation returns the week number for each date field.
db.deliveries.aggregate( [
{
$project: {
_id: 0,
city: "$city",
weekNumber: { $isoWeek: "$date" }
}
}
] )
The operation returns the following results:
{ "city" : "Boston", "weekNumber" : 43 }
{ "city" : "Detroit", "weekNumber" : 33 }