The invention provides methods of time-wise data reduction that include the steps of inputting data from a source; summarizing that data according to one or more selected epochs in which it belongs; and generating for each such selected epoch one or more RDF triples characterizing the summarized data. The data source may be, for example, a database, a data stream or otherwise. The selected epoch may be a second, minute, hour, week, month, year, or so forth. The triples may be output in the form of RDF document objects. These can be stored, for example, in a hierarchical data store such as, for example, a WebDAV server. Triples parsed from the document objects may be maintained in a relational store that is organized, for example, according to a hashed with origin approach.