Explore topic-wise InterviewSolutions in .

This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.

1.

How Does Tuple-oriented Relational Calculus Differ From Domain-oriented Relational Calculus?

Answer»

The tuple-oriented calculus uses a tuple variables i.e., variable whose only permitted values are TUPLES of that relation. E.g. QUEL

The DOMAIN-oriented calculus has domain variables i.e., variables that range over the UNDERLYING domains INSTEAD of over relation. E.g. ILL, DEDUCE.

The tuple-oriented calculus uses a tuple variables i.e., variable whose only permitted values are tuples of that relation. E.g. QUEL

The domain-oriented calculus has domain variables i.e., variables that range over the underlying domains instead of over relation. E.g. ILL, DEDUCE.
Discussion
2.

What Is Vdl (view Definition Language)?

Answer»

It SPECIFIES USER views and their mappings to the CONCEPTUAL SCHEMA.

It specifies user views and their mappings to the conceptual schema.
Discussion
3.

What Is Ddl (data Definition Language)?

Answer»

A DATA BASE schema is specified by a set of definitions EXPRESSED by a special LANGUAGE called DDL.

A data base schema is specified by a set of definitions expressed by a special language called DDL.
Discussion
4.

What Is Multivalued Dependency?

Answer»

Multivalued dependency denoted by X-->Y specified on relation schema R, where X and Y are both subsets of R, SPECIFIES the following CONSTRAINT on any relation r of R: if two tuples t1 and T2 exist in r such that t1[X] = t2[X] then t3 and t4 should also exist in r with the following properties

  • t3[x] = t4[X] = t1[X] = t2[X]
  • t3[Y] = t1[Y] and t4[Y] = t2[Y]
  • t3[Z] = t2[Z] and t4[Z] = t1[Z]

where [Z = (R-(X U Y)) ]

Multivalued dependency denoted by X-->Y specified on relation schema R, where X and Y are both subsets of R, specifies the following constraint on any relation r of R: if two tuples t1 and t2 exist in r such that t1[X] = t2[X] then t3 and t4 should also exist in r with the following properties

where [Z = (R-(X U Y)) ]
Discussion
5.

When Is A Functional Dependency F Said To Be Minimal?

Answer»
  • Every DEPENDENCY in F has a single attribute for its right HAND side.
  • It cannot replace any dependency X -->A in F with a dependency Y--> A where Y is a proper subset of X and STILL have a set of dependency that is EQUIVALENT to F.
  • We cannot remove any dependency from F and still have set of dependency that is equivalent to F.
Discussion