Patent ID: 8402015

Claim:
A method for processing stream data assigning time stamps and processing a stream that is a flow of time series data arriving in an ascending order of the time stamps, the method comprising the steps of: preparing operator trees assuming an operator, which is a basic data processing unit, as a node one by one, with respect to each of a plurality of queries in data processing defined by an interaction of the queries and constructing a single operator graph from the plurality of prepared operator trees; assigning an operator execution order based on the inter-operator input and output relation so that an execution order assigned to operators on an output side is larger than an execution order of operators on an input side, with respect to all the operators on the operator graph; extracting an external ignition operator that receives data from the outside of the operator graph and an internal ignition operator that time-limitedly outputs a keeping tuple, from the operator graph and preparing an ignition operator list; extracting a set of the operators configured of ones having the earliest ignition time of the operator belonging to the ignition operator list and constructing an execution operator list, at an execution timing of the query; and executing the operator where the operator execution order assigned to the operator is minimized among the operators belonging to the execution operator list.