Expression

Aggregate expression

Description

An expression can be a field path, a constant, or an aggregate operator. Expressions can nest expressions.

The field path

Expressions use field path notation to specify fields in a record. T he field path is represented by a $ symbol plus the field name or nested field name. N ested field names use points to connect nested levels of fields. If $profile represents the field path of the profile, $profile.name represents the field path of profile.name (the nested name field in the profile field).

Constant

Constants can be of any type. Strings that start with $ are treated as field paths by default, and if you want to avoid this behavior, use AggregateCommand.literal to declare as a constant.

The aggregate operator

AggregateCommand