14. A system, comprising: a memory storing a plurality of instructions; and one or more processors configured to access the memory, wherein the one or more processors are further configured to execute the plurality of instructions to at least: generate an input relation from a continuous input data stream; store the input relation as an external data source in a database of historical data; receive a continuous query that identifies the input relation and a range value window operator associated with the input relation; execute the continuous query to generate an output relation, the continuous query executed by applying the range value window operator on an attribute of the input relation to generate the output relation, the attribute comprising a characteristic of an event associated with the input relation; determine whether the event associated with the input relation occurs within a specified time range defined by the range value window operator; insert or remove the event with respect to the output relation based at least in part on the determination of whether the event associated with the input relation occurs within the specified time range; and provide data records of the output relation, the output relation comprising at least the event when the event was inserted based at least in part on being within the specified range defined by the range value window operator.
14. A system, comprising: a memory storing a plurality of instructions; and one or more processors configured to access the memory, wherein the one or more processors are further configured to execute the plurality of instructions to at least: generate an input relation from a continuous input data stream; store the input relation as an external data source in a database of historical data; receive a continuous query that identifies the input relation and a range value window operator associated with the input relation; execute the continuous query to generate an output relation, the continuous query executed by applying the range value window operator on an attribute of the input relation to generate the output relation, the attribute comprising a characteristic of an event associated with the input relation; determine whether the event associated with the input relation occurs within a specified time range defined by the range value window operator; insert or remove the event with respect to the output relation based at least in part on the determination of whether the event associated with the input relation occurs within the specified time range; and provide data records of the output relation, the output relation comprising at least the event when the event was inserted based at least in part on being within the specified range defined by the range value window operator. 17. The system of claim 14 , wherein the one or more processors are further configured to display the output relation, wherein the output relation comprises a subset of the data records from the input relation whose attribute values lie within a specified range defined by the range window.