Disadvantages of Lossless Decomposition
- Increased Complexity: Lossless decomposition can increase the complexity of the database system, making it harder to understand and manage.
- Increased Processing Overhead: The process of decomposing a relation into smaller relations can result in increased processing overhead. This can lead to slower query performance and reduced efficiency.
- Join Operations: Lossless decomposition may require additional join operations to retrieve data from the decomposed relations. This can also result in slower query performance.
- Costly: Decomposing relations can be costly, especially if the database is large and complex. This can require additional resources, such as hardware and personnel.
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.