1. A data storage and/or retrieval system implemented on one or more digital data processing systems, comprising: storage media comprising a plurality of data tunnels, one or more of said plurality of data tunnels having a plurality of data cells, wherein the plurality of data tunnels include a plurality of entity type data tunnels for each of a plurality of entity types and a plurality of attribute data tunnels for each of a plurality of attributes, wherein a number of data tunnels for each attribute is fixed for a given attribute, wherein each of the data cells contain data associated with a respective instance of an attribute for a respective and distinct instance of an entity type, wherein each of the data cells of the plurality of attribute data tunnels has data for which a respective operator evaluates to a boolean result indicating either the likely possibility or the impossibility of the attribute instance corresponding to said data cell being characterised by said operator for a given set of one or more operands, and a storage engine that is in communications coupling with the storage media and that accesses one or more of the plurality of data tunnels based on one or more of said operators and a given set of one or more operands.