1. A stream data processing computer comprising: a processor; a query execution module to receive an input stream of stream data, manage execution order of operators for executing a query, and output an output stream of stream data, the operators including static recursive execution modules, a judge operator, and a dynamic recursive execution module; and a memory including a temporal store to store data generated in executing the query; wherein the static recursive execution modules are configured to conduct a recursive number of static recursive execution of the query; wherein the judge operator is configured to determine whether a preset condition is met after the recursive number of static recursive execution of the query; and wherein the dynamic recursive execution module is configured, if the preset condition is not met, to continue execution of the query by dynamic recursive execution from a last result of a last static recursive execution module of the static recursive execution modules, based on a dynamic recursive value.