To provide a system allowing a user who is an analyzer to find novel knowledge from time-series data consisting of a series of numerical values and a measuring time thereof, or annotation time-series data obtained by adding additional text data to the time-series data.

A user prepares an interface in which shapes of a plurality of partial time-series data can be input. An apparatus for finding an interesting pattern provides query language for retrieval capable of flexibly expressing combinations of the shapes of the partial time-series data so as to enable a flexible and intuitive retrieval of time-series data. Further, the apparatus finds an association rule between a tag recorded in the database and the shape of the retrieved partial time-series data from the annotation time-series data so as to execute a function that can extract knowledge for presuming an external factor related to numerical recording which is not apparent by only a change in a numerical value.