Advantages of Lossless Decomposition
- Reduced Data Redundancy: Lossless decomposition helps in reducing the data redundancy that exists in the original relation. This helps in improving the efficiency of the database system by reducing storage requirements and improving query performance.
- Maintenance and Updates: Lossless decomposition makes it easier to maintain and update the database since it allows for more granular control over the data.
- Improved Data Integrity: Decomposing a relation into smaller relations can help to improve data integrity by ensuring that each relation contains only data that is relevant to that relation. This can help to reduce data inconsistencies and errors.
- Improved Flexibility: Lossless decomposition can improve the flexibility of the database system by allowing for easier modification of the schema.
Lossless Decomposition in DBMS
The original relation and relation reconstructed from joining decomposed relations must contain the same number of tuples if the number is increased or decreased then it is Lossy Join decomposition.
Lossless join decomposition ensures that never get the situation where spurious tuples are generated in relation, for every value on the join attributes there will be a unique tuple in one of the relations.