Data storage structure in JT logic based databases

For the unique identification more attributes (columns) are applied in rational databases.<br>In practice, attributes within a type are defined in same data table.<br>Introducing new entity attributes requires the modification of the existing data tables and applications that use these data tables.<br>In JT logic based databases, records with the same ID values identify one entity called virtual record.<br>Virtual records with the same value of the “belonging to the virtual data table” attribute form a data table called virtual data table.