08025009 DBMS LAST YEAR QUESTION PAPERS DATABASE MANAGEMENT SYSTEM

    

B.E/B.Tech DEGREE EXAMINATION Nov/Dec 2007

Fifth semester

Computer Science and Engineering

CS1301 -DATABASE MANAGEMENT SYSTEMS

Answer ALL questions

PART A (10 x 2 =20 marks)

1. List any two advantages of database systems.

2. Give the reasons why null values might be introduces into the database.

3. What is static SQL? How does it differ from dynamic SQL?

4. What are the different types of integrity constraints used in designing a relational database?

5. Compare sequential access devices versus random access devices with an example.

6. What can be done to reduce the occurrences of bucket overflows in a hash file organization?

7. Give the ACID properties.

8. State the benefits of strict two-phase locking.

9. What is the need for complex data types?

10. What is data mining?

PART B (5 x 16 = 80)

11. (a) Explain the system structure of a database system with neat block diagram. (16)

(or)

(b) (i) Construct an ER-diagram for hospital with a set of patients and a set of medical doctors. Associate with each patient a log of the various tests and examinations conducted.  

(ii) Discuss on various relational algebra operators with suitable Example.  

12. (a) (i) Consider the employee database, where the primary keys are underlined.

Employee (empname, street, city)

Works (empname, companyname, salary)

Company (companyname, city)

Manages (empname, managername)

And given an expression in SQL for the following queries:

(1) Find the names of all employees who work for First Bank Corporation.

(2) Find the names, street addresses, and cities of residence of all employees who work for First Bank Corporation and earn more than 200000 per annum.

(3) Find the names of all employees in this database who live in the same city as the companies for which they work.

(4) Find the names of all the employees who earn more than every employees of Small Bank Corporation.  

(ii) Discuss the strengths and weaknesses of the trigger mechanism. Compare triggers with other integrity  

(or)

(b) (i) What is normalization? Explain the various normalization

techniques with suitable example. (12)

(ii) Give the comparison between BCNF and 3NF. (4)

13. (a) (i) Explain how the RAID system improves performance and reliability.  

(ii) Describe the structure of B+ tree and list the characteristics of a B+ tree.  

(or)

(b) (i) Explain the steps involved in processing a query.  

(ii) Give the algorithm for hash join.  

14. (a) (i) Describe about the testing of serializability. (6)

(ii) Discuss on two-phase locking protocol. (10)

(or)

(b) (i) Explain the differed and immediate-modification versions of the log-based recovery scheme (10)

(ii) Write the short notes on shadow paging (6)

15 (a) (i) Highlight the features of OODBMS  

(ii) Write short notes on distributed databases  

(or)

(b) (i) Give the structure of XML data. (4)

(ii) Explain the architecture of a typical data warehouse and describe the various components of data warehouse. (12)        

DBMS 2005 Question Paper

QUESTION 1:
What is database?

ANSWER:
A database is a logically coherent collection of data with some inherent meaning, representing some aspect of real world and which is designed, built and populated with data for a specific purpose.

QUESTION 2:
What is DBMS?

ANSWER:
? Redundancy is controlled.
? Unauthorised access is restricted.
? Providing multiple user interfaces.
? Enforcing integrity constraints.
? Providing backup and recovery.

QUESTION 4:
What is a Database system?

ANSWER:
The database and DBMS software together is called as Database system.

QUESTION 5:
Disadvantage in File Processing System?

ANSWER:
? Data redundancy & inconsistency.
? Difficult in accessing data.
? Data isolation.
? Data integrity.
? Concurrent access is not possible.
? Security Problems. .

QUESTION 6:
Describe the three levels of data abstraction?

ANSWER:
The are three levels of abstraction:

? Physical level: The lowest level of abstraction describes how data are stored.

? Logical level: The next higher level of abstraction, describes what data are stored in database and what relationship among those data.

? View level: The highest level of abstraction describes only part of entire database.

QUESTION 7:
Define the "integrity rules"

ANSWER:
There are two Integrity rules.

? Entity Integrity: States that ?Primary key cannot have NULL value?

? Referential Integrity: States that ?Foreign Key can be either a NULL value or should be Primary Key value of other relation.

QUESTION 8:
What is extension and intension?

ANSWER:
Extension -It is the number of tuples present in a table at any instance. This is time dependent.

Intension - It is a constant value that gives the name, structure of table and the constraints laid on it.

QUESTION 9:
What is System R? What are its two major subsystems?

ANSWER:
System R was designed and developed over a period of 1974-79 at IBM San Jose Research Center . It is a prototype and its purpose was to demonstrate that it is possible to build a Relational System that can be used in a real life environment to solve real life problems, with performance at least comparable to that of existing system.

Its two subsystems are

? Research Storage

? System Relational Data System.

QUESTION 10:
How is the data structure of System R different from the relational structure?

ANSWER:
Unlike Relational systems in System R

? Domains are not supported

? Enforcement of candidate key uniqueness is optional

? Enforcement of entity integrity is optional

? Referential integrity is not enforced

QUESTION 11:
What is Data Independence?

ANSWER:
Data independence means that ?the application is independent of the storage structure and access strategy of data?. In other words, The ability to modify the schema definition in one level should not affect the schema definition in the next higher level.

Two types of Data Independence:
? Physical Data Independence : Modification in physical level should not affect the logical level.
? Logical Data Independence : Modification in logical level should affect the view level.

NOTE: Logical Data Independence is more difficult to achieve

QUESTION 12:
What is a view? How it is related to data independence?

ANSWER:
A view may be thought of as a virtual table, that is, a table that does not really exist in its own right but is instead derived from one or more underlying base table. In other words, there is no stored file that direct represents the view instead a definition of view is stored in data dictionary.
Growth and restructuring of base tables is not reflected in views. Thus the view can insulate users from the effects of restructuring and growth in the database. Hence accounts for logical data independence. .

QUESTION 13:
What is Data Model?

ANSWER:
A collection of conceptual tools for describing data, data relationships data semantics and constraints.

QUESTION 14:
What is E-R model?

ANSWER:
This data model is based on real world that consists of basic objects called entities and of relationship among these objects. Entities are described in a database by a set of attributes.

QUESTION 15:
What is Object Oriented model?

ANSWER:
This model is based on collection of objects. An object contains values stored in instance variables with in the object. An object also contains bodies of code that operate on the object. These bodies of code are called methods. Objects that contain same types of values and the same methods are grouped together into classes.

QUESTION 16:
What is an Entity?

ANSWER:
It is a 'thing' in the real world with an independent existence.

QUESTION 17:
What is an Entity type?

ANSWER:
It is a collection (set) of entities that have same attributes.

QUESTION 18:
What is an Entity set?

ANSWER:
It is a collection of all entities of particular entity type in the database.

QUESTION 19:
What is an Extension of entity type?

ANSWER:
The collections of entities of a particular entity type are grouped together into an entity set.

QUESTION 20:
What is Weak Entity set?

ANSWER:
An entity set may not have sufficient attributes to form a primary key, and its primary key compromises of its partial key and primary key of its parent entity, then it is said to be Weak Entity set.

QUESTION 21:
What is an attribute?

ANSWER:
It is a particular property, which describes the entity.

QUESTION 22:
What is a Relation Schema and a Relation?

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

QUESTION 23:
What is degree of a Relation?

ANSWER:
It is the number of attribute of its relation schema.

QUESTION 24:
What is Relationship?

ANSWER:
It is an association among two or more entities.

QUESTION 25:
What is Relationship set?

ANSWER:
The collection (or set) of similar relationships.

QUESTION 26:
What is Relationship type?

ANSWER:
Relationship type defines a set of associations or a relationship set among a given set of entity types.

QUESTION 27:
What is degree of Relationship type?

ANSWER:
It is the number of entity type participating.

QUESTION 28:
What is Data Storage - Definition Language?

ANSWER:
The storage structures and access methods used by database system are specified by a set of definition in a special type of DDL called data storage-definition language.

QUESTION 29:
What is DML (Data Manipulation Language)?

ANSWER:
This language that enable user to access or manipulate data as organised by appropriate data model.

? Procedural DML or Low level: DML requires a user to specify what data are needed and how to get those data.

? Non-Procedural DML or High level: DML requires a user to specify what data are needed without specifying how to get those data.

QUESTION 30:
What is VDL (View Definition Language)?

ANSWER:
It specifies user views and their mappings to the conceptual schema.

QUESTION 31:
What is DML Compiler?

ANSWER:
It translates DML statements in a query language into low-level instruction that the query evaluation engine can understand.

QUESTION 32:
What is Query evaluation engine?

ANSWER:
It executes low-level instruction generated by compiler.

QUESTION 33:
What is DDL Interpreter?

ANSWER:
It interprets DDL statements and record them in tables containing metadata.

QUESTION 34:
What is Record-at-a-time?

ANSWER:
The Low level or Procedural DML can specify and retrieve each record from a set of records. This retrieve of a record is said to be Record-at-a-time.

QUESTION 35:
What is Set-at-a-time or Set-oriented?

ANSWER:
The High level or Non-procedural DML can specify and retrieve many records in a single DML statement. This retrieve of a record is said to be Set-at-a-time or Set-oriented.

QUESTION 36:
What is Relational Algebra?

ANSWER:
It is procedural query language. It consists of a set of operations that take one or two relations as input and produce a new relation.

QUESTION 37:
What is Relational Calculus?

ANSWER:
It is an applied predicate calculus specifically tailored for relational databases proposed by E.F. Codd. E.g. of languages based on it are DSL ALPHA, QUEL.

QUESTION 38:
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.

QUESTION 39:
What is normalization?

ANSWER:
It is a process of analysing 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.

QUESTION 40:
What is Functional Dependency?

ANSWER:
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.

QUESTION 41:
When is a functional dependency F said to be minimal?

ANSWER:
? Every dependency in F has a single attribute for its right hand side.

? We 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.

QUESTION 42:
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)) ]

QUESTION 43:
What is Lossless join property?

ANSWER:
It guarantees that the spurious tuple generation does not occur with respect to relation schemas after decomposition.

QUESTION 44:
What is 1 NF (Normal Form)?

ANSWER:
The domain of attribute must include only atomic (simple, indivisible) values.

QUESTION 45:
What is Fully Functional dependency?

ANSWER:
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.

QUESTION 46:
What is 2NF?

ANSWER:
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.

QUESTION 47:
What is 3NF?

ANSWER:
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.

In other words, if every non prime attribute is non-transitively dependent on primary key.

QUESTION 48:
What is BCNF (Boyce-Codd Normal Form)?

ANSWER:
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.

QUESTION 49:
What is 4NF?

ANSWER:
A relation schema R is said to be in 4NF if for every Multivalued dependency X Y that holds over R, one of following is true

? X is subset or equal to (or) XY = R.

? X is a super key.

QUESTION 50:
What is 5NF?

ANSWER:
A Relation schema R is said to be 5NF if for every join dependency {R1, R2, ..., Rn} that holds R, one the following is true

? Ri = R for some i.

? The join dependency is implied by the set of FD, over R in which the left side is key of R.

B.E. (Fifth semester) EXAMINATION, June 2006

(Common for CS/IT Engg.)

(DATABASE MANAGEMENT SYSTEM)

(CS/IT (503))

Note:      Attempt any five questions. All question carry equal marks.

1. (a)    What are the responsibilities of DBA ? Explain .

(b)    Write difference between the following  :

(i)     Logical and physical data independence

(ii)    Database and physical data independence

2. (a)   Define and discuss main constraints on the following by giving example :

(i)     Specialization

(ii)     Generalization

(iii)   Aggregation

(b)   Draw an E-R diagram of university by determining entities of interest and the relationship that Exist between these entities .

3. (a)   Explain the distinction between the representation of association and relationship in the network And hierarchical models.

(b)   Explain about the following relational algebra operators by giving suitable example :

Union ,division,rename,difference

4.(a)   Consider the following Employee database :

Employee (Emp-name,street,City)

Work (Emp-name, company name- Salery)

Company  (Company ­­­–name, city)

Manages (Emp -name ,managers – name)

Write expression in SQL and QUEL for the following queries :

(i)    Find all employees who live in the city where the company for which they work is located .

(ii)    Find all employees who live in the same city and on the same street as their managers.

(iii)    Find all employees in the database who do not work for ABC corporation .

(iv)    Find all employee names who earn more than every than every employee of ABC  corporation .

(v)     Find all company names located in every city in which ABC corporation is located.

5.(a)    Prove or disprove the following inference rules for functional dependencies :

(i)  { W ? Y, X?Z }     |= { WX ?Y}

(ii)  {X ? Y} and Y > Z |={X ? Z}

(iii) { X ? Y, Y?Z}       |= {X? YZ}

(iv) {X?Z , Y?Z}         |={X?Y}

(v)  { XY ?Z, Z?W}    |= {X?W}

(b)     What are interface rules for multivalued  depencies ? Explain .

6.(a)     Describe NULL value and dangling tuple problems.

(b)     What is a canonical cover ? If

F={A?BC, CD ? E, E ?C,D? AEH; ABH ?BD, DH ? BC }

Show that the non-redundant cover for F is

{ A?BC, E ? C,D ? AEH , ABH ? BD}

7.(a)     What is serializability ? Write an algorithm for testing conflict serializabilty of a schedule .

(b)     Describe different types of transaction failure . What is meant by catastrophic failure ?

8.(a)     Write short notes on any two of the following :

(i) Various data models

(ii) Security and integrity constraints

(iii) Object- oriented database systems

(iv)  QBE

B.E. (Fifth semester) EXAMINATION, June 2007

(Common for CS/IT Engg.)

(DATABASE MANAGEMENT SYSTEM)

(CS/IT (503))

Note:      Attempt any five questions. All question carry equal marks.

1.    (a)   Discuss main categories of data models.

(b)   Explain the following terms :

(i) Database schema

(ii) data independence

©     Explain the difference between the two-tier and three-tier client server architecture.

2.  (a)     Construct an E-R diagram for a hospital with set of patients and set of medical doctors.

Associate with each patient a log of various tests and examination conducted.

(b)     What is subclass ? When is subclass needed in data modeling ?  Explain is-a relationship.

3.  (a)     Differentiate between the following :

(i) Super key and Primary key

(ii) Strong entity and weak entity

(iii) Generalization and Specialization

(iv) User defined and attribute specialization

(b)   Discuss entity and referential integrity constraints . Why each is considered important ?

4.(a)    What is Union compatible ? Why do the Union, intersection and set-difference operation require

That the relation on which they are applied are union compatible ?

(b)     Explain with respect to tuple calculus :

(i) tuple variable    (ii) range relation   (iii) atom formula   (iv) expression

(iv ) (Exsitential quantifier ) and ?/ (universal quantifier) .

5.   Consider  the following database primary key underlined :

Employee (ENO. DOB, ADDRESS, SEX, SALARY, NAME, DNOSUPER END).

Department (DNO, D Name, MGRENO, MGR start date )

Dept-location (DNO,Diocation)

Project (PNAME, PNO, Placation, DNO)

Works (ENO, PNO, hours)

Department (ENO, dep-name, Sex, bate, relationship)

For each of the following quires  given expression in SQL and relation algebra :

(a)  Retrieve the names if all employees in department

(b)  List the name of all employee who have no dependents

(c)  Retrieve the name of all employee who do not work on any project

(d)  Retrieve the average salary of all female employees.

(e)  Find the names of all employee who work on at lest one project locted in Hyderabad .

(f)  Write SQL, DDSL statements for the above database.

6. (a)  Consider the relation R (A, B, C, D, E, G, H, I, J)and set of functional dependencies :

F = { {A, B} ? {C},{A} ?{D,E}, {B} ? {F}, {F}

? {G,H}, {D}?{I,J} }

What is the key of R , Decompose R in 2 NF and 3 NF ?

(b)  Explain the following :

(i)   Trivial dependency

(ii)  Lossless decomposition

(iii)  Dependency preservation

(iv)   Functional dependency

(v)    Multivalued dependency

7. (a) Explain data fragmentation ,replication and allocation techniques for distributed database design.

(b) Explain, join natural join, outer join, full outer join, lft outer join and right outer join with example .

8.  Write short notes on any four of the following :

(i) Oracle tools.

(ii) Object orient database design

(iii)  Security constraint in DBMS

(iv) Role of DBA

(v) Database management system architecture.

B.E. (Fifth semester) EXAMINATION, June 2008

(Common for CS/IT Engg.)

(DATABASE MANAGEMENT SYSTEM)

(CS/IT (503))

Note:      Attempt one question from each unit. All question carry equal marks.

1.           Supreme products manufactures products like pressure cookers , cook-wavers ,water purifiers, food processor etc. the company markets its products to wholesalers all over the country and dealers sell them to .customers. the company has five regional offices and many sakes persons are attached to regional offices. Sales persons contact dealers and explain about products, incentive offered,traning program for wholesaler and demonstration for customer etc. Dealers places orders with the sales persons attached with the regional office of their location . After receiving goods they make payment , which may be in a installment company would like to develop a system to monitor sales of different products , Performance of salespersons and order from wholesalers. Do the following :

(a)     Identify entities , attributes and relationship giving functionalities and draw an E-R diagram for the system.

(b)    Convert this to relation table explaining the logic involved  .

2   (a) Define the following with respect  to an diagram. Explain the manner in which each is mapped to a table . Illustrate with an example :

(i) Relationship set   (ii) Aggregation    (iii) Multivalued attribute

(b)     Describe five main function of a database administrator .

3.   (a) Define primary key, candidate key, foreign key and super key with in example. Discuss the type of integrity constrains that must be checked for the update operation insert and delete. Give examples.

(b)   Differentiate between intension and extension.

4.   (a) Define the  following operation of relation algebra and given an explain each :

(i) Division    (ii) Natural Join

(b)  What is recursive closure? Why is not possible to define this operation in realation algebra?

5.         Consider the following relation with key underline :

Street (name, location, city)

House (number, street number)

Lives (name, house _number )

(a)   Define the above relation as tables in SQL making real world assumption about the type of fields.

Define the primary keys and forging key .

(b)   For the above relation answer the following queries in SQL :

(i) Get the names of person who live in the street name “Mahatma Gandhi”

(ii) Get the house numbers street wise.

(iii) Get the number of house which are not occupied.

©      What is the NULL?  Give an example to illustrate testing for NULL in SQL.

6.   (a) Explain the EXISTS and UNIQUE functions of SQL. Get an example for each .

(b)  R(R,B) and S(A,C) be two relations. Given relational algebra expression for the following domain calculus expression :

(i) {<a>| b (<, b> ?r ^ b = 17)}

(ii)  {<a, b, c> |<a, b > ?r ^ <a , c, > ?s}

7.   (a) Prove that the relation  which is in 4 NF must be in BCNF.

(b) Given an example of a relation schema R’ and set F’ of functional dependencies such that there are least three distinct lose less join decomposition of R’ into BCNF.

8. (a) What are the advantages of the three locking protocol over the two phase locking protocol?

Explain the phantom phenomenon.  Why this phenomenon may lead to an incorrect concurrency execution despite the use of a protocol that ensures sreializability?

(b)  Explain the recovery process after system failure using checkpoint.

9. (a) Explain the importance of trigger with an example in ORICAL .

(b) How is the database organized in oracle?

10 (a) How sequences are created in oracle? Explain

(b) How do you create forging key in MS access?

(c) Write the utility of micros in MS access.

(d) Explain compact and repair database utility of MS access.

B.E. (Fifth semester) EXAMINATION, Dec, 2008

(Common for CS/IT Engg.)

(DATABASE MANAGEMENT SYSTEM)

(CS/IT (503))

Note:      Attempt all question . All question carry equal marks.

1.    (a)    Give the proper definition of the following :

(i)     Degree of relation

(ii)    Strong Entity set

(iii)    Physical Schema

(iv)   Instance

(b)    Give example of the following :

(i)     A many to many relationship in which one of the participants is another relationship.

(ii)    A subtype that has an associated weak entity that does not apply to the super type.

2.  (a)    Explain referential integrity with suitable example.

(b)    What are the responsibilities of database Administrator ? Explain them in brief .

3.  (a)    Discuss the type of integrity constraints that must be checked for the update operations insert and delete . Give example.

(b)    R(A,B) and S(A,C) be two relations. Give relational algebra expressions for te following domain Calculus expressions.

(i)  {<a>| b (<a, b > ?r ^ b = 17)}

(ii)  {<a, b , c> |<a, b> ?r ^ <a, c> ?s}

(iii)  {<a> |b( c {<a, b> ?r) ^ <a, c>   ?s) } }

4. (a)   Difference between the following :

(i)  Intension and Extension

(ii)  Natural join and theta join

(iii) Primary Key and alternative  key.

(b)   Explain the use of division relational operator with example.

5. (a)    Differentiate between tuple oriented and domain oriented relational calculates.

(b)   Consider te following relational database :

Employee (employee-name ,street, city)

Works (employee name_ company _name, salary)

Company (company _name, city)

Manages (employee_name,manager_name)

Write SQL for the following queries :

(i)   Find the name of all employee In this database who live in the same city as the cowpony for which they work.

(Ii)   Find the name of all employee  who live in the same city and on the same street as do their Manager.

(iii)   Find the name of all employees in this database who do not work for the company ‘FBC’

6. (a)  What is NULL? Give an example to illustrate testing for NULL in SQL .

(b)  Describe substring comparison in SQL ? For the relation person (name,addresswrite a SQL which Retrieves the names of people whose name begin with ‘A’ and address contains ‘Bangalore’ .

7. (a)  Explain the recovery process after system failure using checkpoint.

(b)  Discuss the factor that does not apper in centralized system that affect concurrency control and recovery in distributed system.

8. (a)   Explain how the concept of object identity in the object oriented models differs from the concept of tuple equality in the relational model.

(b)  Prove that a relation which is in 4NF must be in a BCNF .

9. (a) Explain the following feature of ORACLE:

(I)  Sequence   (ii)  Triggers   (iii)  SQL loader

(b)   How is the database organized in oracle ?

10. (a)  How will you make the relationship between two tables in MS ACCESS ? Write steps .

(b)  Explain the various data types available in MS ACCESS.

  

1)Why DBMS is required? Explain its necessity.

2)Discuss the role of Database administrator and Database engine.

3)Define the following:

(a)Primary key and Foreign key

(b)Schema and Sub Schema

4)Explain the SELECT statement in SQL with example.

5)Explain the Multilevel dependency with example.

6)Explain the concept of Distributed Database.

7)Briefly discuss about Knowledge Database.

1)Explain the Database model and its implementation in detail.

2)Explain the various File organizations for conventional DBMS.

3)What is Normalization? Explain the various Normal Forms with example.

4)Explain the significance of Relational Database.

5)Explain various DML Commands in SQL with example.

6)Describe in detail about Object Oriented Database.

7)Explain the working principles of Client/Server Database.