Interview Questions.

Question 1. When Is A Functional Dependency F Said To Be Minimal?

Answer :

Every dependency in F has a single characteristic for its right hand aspect.
It can not replace any dependency X -->A in F with a dependency Y--> A where Y is a right subset of X and now have a hard and fast of dependency that is equal to F.
We can't remove any dependency from F and also have set of dependency this is equivalent to F.
Question 2. What Is Operational Data Store?

Answer :

An operational statistics save (or "ODS") is a database designed to combine records from more than one assets to make analysis and reporting easier.

Data Warehouse ETL Toolkit Interview Questions
Question 3. What Is Multivalued Dependency?

Answer :

Multivalued dependency denoted by means of X-->Y particular on relation schema R, where X and Y are both subsets of R, specifies the subsequent 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 residences

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]
in which [Z = (R-(X U Y)) ]

Question 4. What Is Ddl (facts Definition Language)?

Answer :

A facts base schema is detailed by way of a fixed of definitions expressed by way of a special language referred to as DDL.

Data Warehouse ETL Toolkit Tutorial
Question 5. What Is Vdl (view Definition Language)?

Answer :

It specifies person perspectives and their mappings to the conceptual schema.

Data Warehousing Interview Questions
Question 6. What Is Degree Of A Relation?

Answer :

It is the variety of characteristic of its relation schema.

Question 7. What Is A Relation Schema And A Relation?

Answer :

A relation Schema denoted via R(A1, A2, ?, An) is made of the relation call R and the listing of attributes Ai that it incorporates. A relation is defined as a fixed of tuples. Let r be the relation which includes set tuples (t1, t2, t3, ..., tn). Each tuple is an ordered list of n-values t=(v1,v2, ..., vn).

Data Warehousing Tutorial Data Center Management Interview Questions
Question eight. How Does Tuple-orientated Relational Calculus Differ From Domain-oriented Relational Calculus?

Answer :

The tuple-orientated calculus uses a tuple variables i.E., variable whose handiest authorized values are tuples of that relation. E.G. QUEL

The area-orientated calculus has area variables i.E., variables that variety over the underlying domain names rather than over relation. E.G. ILL, DEDUCE.

Question 9. What Is Relationship?

Answer :

It is an association amongst two or greater entities.

Relationship Set - The collection (or set) of similar relationships.

Relationship Type - Relationship kind defines a hard and fast of associations or a dating set among a given set of entity kinds.

Degree of Relationship Type - It is the quantity of entity kind taking part.

Data Stage Interview Questions
Question 10. What Is Normalization?

Answer :

It is a manner of analysing the given relation schemas primarily based on their Functional Dependencies (FDs) and primary key to gain the houses.

Minimizing redundancy
Minimizing insertion, deletion and replace anomalies.
Data Structure & Algorithms Tutorial
Question eleven. What Is Functional Dependency?

Answer :

Functional dependency is denoted with the aid of X --> Y between  sets of attributes X and Y that are subsets of R specifies a constraint at the feasible tuple that could shape a relation kingdom r of R. The constraint is for any two tuples t1 and t2 in r if t1[X] = t2[X] then they have got t1[Y] = t2[Y]. This way the fee of X component of a tuple uniquely determines the value of factor Y.

Data analyst Interview Questions