1. What is Lossless join property?
It guarantees that the spurious tuple generation does not occur with respect to relation schemas after decomposition.
2. What is 1 NF (Normal Form)?
The domain of attribute must include only atomic (simple, indivisible) values.
3. What is Fully Functional dependency?
It is based on concept of full functional dependency. A functional dependency X Y is full functional dependency if removal of any attribute A from X means that the dependency does not hold any more.
4. What is 2NF?
A relation schema R is in 2NF if it is in 1NF and every non-prime attribute A in R is fully functionally dependent on primary key.
5. What is 3NF?
A relation schema R is in 3NF if it is in 2NF and for every FD X A either of the following is true
- X is a Super-key of R.
- A is a prime attribute of R.
6. What is BCNF (Boyce-Codd Normal Form)?
A relation schema R is in BCNF if it is in 3NF and satisfies an additional constraint that for every FD X A, X must be a candidate key.
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