layer definition

A layer definition is a SQL WHERE clause for a feature layerA feature layer (client-side) is a data layer that can access and display features from a feature service that has the same type of geometry and attribute fields.Learn more that is used to select a subset of featuresA feature is a single record, also known as a row, that represents a real-world entity. It typically contains a geometry (point, multipoint, polyline, or polygon) and attributes but it can also contain just attributes.Learn more from a feature serviceA feature service is a data service that provides access to spatial and non-spatial data in feature layers, feature layer views, and tables.Learn more.