Technical Interview Questions and Answers :: iGate
Tot. Mock Test: 11
Total Qs: 160+
It is an association among two or more entities.
The collection (or set) of similar relationships.
Relationship type defines a set of associations or a relationship set among a given set of entity types.
It executes low-level instruction generated by compiler.
It is a process of analyzing the given relation schemas based on their Functional Dependencies (FDs) and primary key to achieve the properties
> Minimizing redundancy
> Minimizing insertion, deletion and update anomalies.
A Functional dependency is denoted by X->Y between two sets of attributes X and Y that are subsets of R specifies a constraint on the possible tuple that can form a relation state r of R. The constraint is for any two tuples t1 and t2 in r if t1[X] = t2[X] then they have t1[Y] = t2[Y]. This means the value of X component of a tuple uniquely determines the value of component Y.
It guarantees that the spurious tuple generation does not occur with respect to relation schemas after decomposition.
The domain of an attribute must include only atomic (simple, indivisible) values.
It is based on the 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.
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.