Database Management System Interview Question

-:Database Management System Interview Question:-
-:डेटाबेस प्रबंधन प्रणाली साक्षात्कार प्रश्न :-

1. What is database system?

Ans: A database system is a collection of interrelated data and a set of programs that allow user to access  and modify  this data.The major purpose of this system is  provied user with an abstract view of data.

2.What is database?

Ans: A database is a collection of data,which conatain some information.It is organized,taht easily can be access,modify,and update.

3.What is DBMS?

Ans:The full from of DBMS is data base manage ment system.it is allow user to edit,update,creat and  maintain .

4.What is Data Model?

Ans:A data model is a basically abstract model.It can be related as real world entities scuh as car it has it’s own size color function etc.i.e it has it’s own properties.

5.What is Object Oriented model?

Ans:An objects ghas its own programs like value,size ,color etc taht value are stored in it’s instance variables,it has it’s own code which can operate with the object.those bodies are basically called mathod.basically Object Oriented model is an approach to modeling an application that is used at the beginning of the Sdlc(software devolopment life cycel).

6.what is data abstraction?

Ans:Sometime developer hide the complex city from user.The need for efficiency has lead designers to use complex data structure to represent data in database.that process is called data abstraction.

7.How many level of data abstraction There ?

Ans: three type of data abstraction 1.physical level,2.logical level,3.view level.

8.What are the advantages of DBMS?

Ans:1.Data are organized, 2.It control Redundancy,3.Data can shere,4.Data consistency is obtained,5.backup and recovery procidures.

9.What is a Database system?

Ans:When a databsae interact with a DBMS application  and work together that is called Database system.

10.What is schema ?

Ans:The overall desing of the databse is called schema.they are chaanae infrequently .

11.What is DML?

Ans: it is data manipulation language.it is enbles ueser to access or manipulate data.

12.What is an Entity?

Ans:Basically entity isa  part of object,it can say it is a properties of object.

13.What is Normalization

Ans:It is an another method for desingning a relationla database is to use a process commonly known as normalization.

14. Which of the following language in Databas is used for define tables ?1.DDL 2.DML 3.DCl 4.None of these 

Ans:DDl(Data-Dafination language).Sqlprovieds a rich DDl that allows one to define Tables,integity constrains Etc.

15.What is E-R model?

Ans:This model describes the relationship between entities.That entities are the part of object .Basically E-R Model is uused to describe relation of an object’s entity which is based on real world.

16.What is function dependencies ?

Ans:>function dependency is an extension of the nation of “key”    >function dependency it constrains on set of legal relations.

17.What is a query?

Ans:query is a type of command that allow user to edit ,update,sort ,search,maintain etc on a dtabase system.

18.What is an attribute?

Ans:a properties of an object that describe aa perticular entity. It is a perticular property.

19.What is Index?

Ans:a Datastructure technique which help user to retrieve records from the tabelof an Database.It is similer to an book index.

20.What is Report Writers ?

Ans:To create any reporst in databse msot of the DBMS provied report writer tools.once a report created it can be used any time.It can be modifyed easily.

21.What is Data indipendence ?

Ans:in the DBMS The separation of datastructure of a database from the corosponding application programs tahst use the data is called Data indipendence.

22.How do you communicate with an RDBMS ?

Ans: There is a process to communicate with the relational Database management System in a Databaseis called structure query language (SQL)codeing.

23.What is VDL ?

Ans:The full name of VDL is View Defination language.it is allow user to Vies and mapping to the conceptual schema in a database.

24.What is Trigger?

Ans:It is process of SQL that initiates action like INSERT,UPDATE,DELETE in an Event.It works when an Event occurs.

25.What is a view?

Ans:It is a searchable objects in a database.it is defiend by a query.it is basically a vartual table.By join the view can combine two or more table in a database.

26.What is SQL?

Ans:SQL means structure query language.it isa a kind of programming language that used in desinge or managing data in relational datbase manage ment system .used for communiate with the database.

27.What is Anomalles ?

Ans:An anomaly is a variation with respect to a database maintenance .In database when Upadte ,insetr,delete operation are performd it is desirable that these operation should be in a mimum time,cost effective,predictable and efficient.

28.What is normalization ?

Ans:Realtions resulting from a well written E-R design may still have some undesirable properties.To remove this kind of properties user applied a process that callledNormalization.

29.How many normailization from are there ?1.3 ,2.5, 3.2, 4.none of these

Ans:2.5(1NF,2NF,3NF,BCNF,4NF,5NF)

30. What is meant by query optimization?

Ans:while evaluating a query which have the least estimated cost that help to efficentexecution plan is  refer to as a query Optimization.

31.What is 1 NF (Normal Form)?

Ans:1 Nf is the first normailization from of a database table.in this normilization teechnique user have to eliminate the duplicate colum from the one same table and after separating tabel of ecah group identify each group row with a unique row value by using a primary key.that would be the unic columm.

32.What is 2NF?

Ans: To make 2nd normal from of a dDatabase we  have to check Every non attribute columm or Non prime attribute of A in a relation R fully depend on a primary Key.

33.What is 3NF?

Ans:First it have to be in 2nd NF the have to check if there is any depencny therre if there then have to make non functional dependencies between Two or morenon primary Key attributes.

34.What is view serializable?

Ans:in a database is schedule is to be said  serializable when its view serialize is equivalent to the other serial schedule.I.E. the view will be same as schedule serial.

35.What is a foreign key?

Ans:In the term of relational database a foreign key is an another type pf primary key that is the unic key or uniquely identifies a row of another table or same Table.