Identifying, Managing, and Accessing Undefined Tuple States in Relational Databases

Current trends in relational databases are formed by storing whole state evolution with emphasis on temporality. Input data must be proper, obtained in an adequate time, but mostly consistent. It can result in managing multiple undefined states, commonly represented by the NULL notation, which cannot be mathematically compared. Its reference using the index is also limited. Nowadays, NULL values are transformed using the trigger or by replacing them by the default values. Both strategies bring additional storage demands. Our proposed solution remains the original data but extends the index structure using the External or Referencer modules to ensure identification and performance. Whereas the origin of the NULL value can differ, emphasis is done on the categorization supervised by the multi-indexing layer or bitmap category mapper.