SortByCount constructor
SortByCount(
- dynamic expression
Creates $sortByCount
aggregation stage
expression
- expression to group by. You can specify any expression
except for a document literal.
To specify a field path, use Field. For example:
Dart code:
SortByCount(Field('employee')).build()
Equivalent mongoDB aggregation stage:
{ $sortByCount: "$employee" }
Although you cannot specify a document literal for the group by
expression, you can, however, specify a field or an expression that
evaluates to a document. For example, if employee and business fields are
document fields, then the following is a valid argument to
$sortByCounts
:
Dart code:
SortByCount(MergeObjects([Field('employee'), Field('business')])).build()
Equivalent mongoDB aggregation stage:
{ $sortByCount: { $mergeObjects: [ "$employee", "$business" ] } }
Implementation
SortByCount(expression) : super('sortByCount', expression);