Abstract: A system and method for implementing incremental evaluation that is advantageous over nonincremental evaluation. The system and method incrementally maintain each individual aggregate value, for non-nested queries, using a constant amount of work.

Abstract: A system and method for implementing incremental evaluation that is advantageous over nonincremental evaluation. The system and method incrementally maintain each individual aggregate value, for non-nested queries, using a constant amount of work.

Abstract: Techniques for collecting and displaying sensor data captured by a spatially and temporally representative sample of sensors requested in a search query are described. The sensors are represented in an index structure (e.g., a data tree) having a plurality of leaf nodes and internal nodes. The leaf nodes are associated with sensors and the internal nodes are allotted with caches having cache slots for storing sensor data with various expiry times. In response to a query, the index structure is leveraged to identify a set of nodes associated with sensors of a user selected spatial region. Sensor data having an expiry time greater than a user specified expiry time is then collected from one or more cache slots of the set of nodes. In this manner, the number of sensors to be probed to collect the sensor data is reduced.

Abstract: Techniques for collecting and displaying sensor data captured by a spatially representative sample of sensors requested in a search query are described. The sensors are represented in an index structure (e.g., a data tree). In response to a query, the index structure is leveraged to identify a subset of sensors that exhibits a similar spatial distribution to the original full set of sensors. Sensor data is then collected from the subset of sensors by probing the sensors or retrieving recently cached data located by the index and returned to satisfy the query. In this manner, the number of sensors to be probed is reduced, thereby reducing latency involved with polling a large number of sensors and making the search process more efficient.

Abstract: Techniques for collecting and displaying sensor data captured by a spatially and temporally representative sample of sensors requested in a search query are described. The sensors are represented in an index structure (e.g., a data tree) having a plurality of leaf nodes and internal nodes. The leaf nodes are associated with sensors and the internal nodes are allotted with caches having cache slots for storing sensor data with various expiry times. In response to a query, the index structure is leveraged to identify a set of nodes associated with sensors of a user selected spatial region. Sensor data having an expiry time greater than a user specified expiry time is then collected from one or more cache slots of the set of nodes. In this manner, the number of sensors to be probed to collect the sensor data is reduced.

Abstract: Techniques for collecting and displaying sensor data captured by a spatially representative sample of sensors requested in a search query are described. The sensors are represented in an index structure (e.g., a data tree). In response to a query, the index structure is leveraged to identify a subset of sensors that exhibits a similar spatial distribution to the original full set of sensors. Sensor data is then collected from the subset of sensors by probing the sensors or retrieving recently cached data located by the index and returned to satisfy the query. In this manner, the number of sensors to be probed is reduced, thereby reducing latency involved with polling a large number of sensors and making the search process more efficient.