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Field class

Represents a reference to a field in a Firestore document, or outputs of a Pipeline stage.

Field references are used to access document field values in expressions and to specify fields for sorting, filtering, and projecting data in Firestore pipelines. You can create a `Field` instance using the static method:

Signature:

typescript

export declare class Field extends Expression implements Selectable

Extends: Expression

Implements: Selectable

Properties

Property	Modifiers	Type	Description
alias		string
expr		Expression
expressionType		ExpressionType
fieldName		string
selectable		true

Methods

Method	Modifiers	Description
geoDistance(location)		<b><i>(Public Preview)</i></b> Evaluates to the distance in meters between the location specified by this field and the query location.

Field.alias

Signature:

typescript

get alias(): string;

Field.expr

Signature:

typescript

get expr(): Expression;

Field.expressionType

Signature:

typescript

readonly expressionType: ExpressionType;

Field.fieldName

Signature:

typescript

get fieldName(): string;

Field.selectable

Signature:

typescript

selectable: true;

Field.geoDistance()

This API is provided as a preview for developers and may change based on feedback that we receive. Do not use this API in a production environment.

Evaluates to the distance in meters between the location specified by this field and the query location.

This Expression can only be used within a Search stage.

Signature:

typescript

geoDistance(location: GeoPoint | Expression): Expression;

Parameters

Parameter	Type	Description
location	GeoPoint \| Expression	Compute distance to this GeoPoint.

Returns:

Expression

Example

typescript

// Create a Field instance for the 'name' field
const nameField = field("name");

// Create a Field instance for a nested field 'address.city'
const cityField = field("address.city");