<XML><RECORDS><RECORD><REFERENCE_TYPE>15</REFERENCE_TYPE><REFNUM>5473</REFNUM><AUTHORS><AUTHOR>Mcgregor,D.</AUTHOR><AUTHOR>Cockshott,P.</AUTHOR><AUTHOR>Wilson,J.</AUTHOR></AUTHORS><YEAR>2001</YEAR><TITLE>Databases</TITLE><PLACE_PUBLISHED>US Patent 6169990 British Patent, Volume BP 9604522.4</PLACE_PUBLISHED><PUBLISHER>Academic Press</PUBLISHER><LABEL>Mcgregor:2001:5473</LABEL><KEYWORDS><KEYWORD>compression</KEYWORD></KEYWORDS<ABSTRACT>A computer database for storing information in tuple form wherein each tuple comprises fields with corresponding fields in the tuples constituting a column, generates for each data domain a domain dictionary which matches each distinct data value in that domain with a corresponding distinct token, and stores each domain dictionary. A tokenised store for each data field column is created. All of the tokens for a domain are initially of the same size being substantially the minimum size necessary to provide the required plurality of distinct tokens for initialize size of that domain. When further tuples are received for storage for each field of the tuple, the data value is compared in the corresponding domain dictionary. If no match is found, a new token within the existing token size is generated and added to the domain dictionary, but if all tokens within the existing token size are utilised a new token is generated having a size which is at least 1-bit wider than previously, such broadened token being entered into a new tokenised store for that column.</ABSTRACT></RECORD></RECORDS></XML>