16. A computer-implemented method, comprising: receiving a continuous query configured to process data objects associated with business event data, the continuous query including an identifier of historical data associated with the stream; generating a data object to include at least a portion of the historical data and that is configured to receive incoming events of the steam that are within a window that corresponds to the window size; receiving a window size configured to identify a bounded range of the data object to process; initializing the continuous query with the data object to process at least the portion of the historical data at the identified stateful operator based at least in part on the window size; and evaluating the data object using the continuous query based at least in part on the window size.
19. The computer-implemented method of claim 16 , further comprising determining an optimal amount of the historical data with which to initialize the continuous query based at least in part on the window size.