1. A method comprising, by one or more computer systems: from an indexer in a sensor network, accessing a set of sensor data that comprises: a plurality of sensor data aggregated together from a plurality of sensors in the sensor network; one or more time stamps for the sensor data; and metadata for the sensor data identifying one or more pre-determined attributes of the sensor data; at the indexer, generating an index of the set of sensor data according to a multi-dimensional array configured for querying of the set of sensor data along with a plurality of other sets of sensor data, one or more first ones of the dimensions of the multi-dimensional array comprising time and one or more second ones of the dimensions of the multi-dimensional array comprising one or more of the pre-determined sensor-data attributes; and from the indexer, communicating the index of the set of sensor data for use in responding to one or more queries of the set of sensor data along with a plurality of other sets of sensor data.