Department of Computer Science and Engineering

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Department of Computer Science and Engineering Course Name : Database Management Systems Course Number : A55025 Course Designation : Core Prerequisites : Data Structures II B Tech II Semester (2015-2016) A.MalliKarjuna Reddy Assistant Professor

SYLLABUS Introduction to Database System Concepts: Database-System Applications, Purpose of Database Systems, View of Data, Database Languages, Relational Databases, Database Design, Data Storage and Querying, Transaction Management, Database Architecture, Data Mining and Information Retrieval, Spatial Databases, Database Users and Administrators, History of Database Systems. Unit I RELATIONAL DATABASES Introduction to the Relation Models: Structure of Relational Databases, Database Schema, Keys, Schema Diagrams, Relational Query Languages, Relational Operations. Introduction to SQL: Overview of the SQL Query Language, SQL Data Definition, Basic Structure of SQL Queries, Additional Basic Operations, Set Operations, Null Values, Aggregate Functions Nested Sub queries, Modification of the Database. Unit II Intermediate SQL: Join Expressions, Views, Transactions, Integrity Constraints, SQL Data Types and Schemas, Authorization. Advanced SQL:, Functions and Procedures, Triggers, Cursors, Formal Relational Query Languages: The Relational Algebra, The Tuple Relational Calculus, The Domain Relational Calculus. DATABASE DESIGN Unit III Unit IV Database Design and the E-R Model: Overview of the Design Process, The Entity- Relationship Model, Constraints, Removing Redundant Attributes in Entity Sets, Entity- Relationship Diagrams, Reduction to Relational Schemas, Entity-Relationship Design Issues, Extended E-R Features, Alternative Notations for Modeling Data, Other Aspects of Database Design. Relational Database Design: Features of Good Relational Designs, Atomic Domains and First Normal Form, Decomposition Using Functional Dependencies, Functional- Dependency Theory, Algorithms for Decomposition, Decomposition Using Multi valued Dependencies, More Normal Forms, Database-Design Process. DATA STORAGE AND QUERYING Storage and File Structure : Overview of Physical Storage Media, Magnetic Disk and Flash Storage, RAID, Tertiary Storage, File Organization, Organization of Records in Files Data-Dictionary Storage, Database Buffer. Indexing and Hashing: Basic Concepts, Ordered Indices, B+-Tree Index Files, B+-Tree Extensions, Multiple-Key Access, Static Hashing, Dynamic Hashing, Comparison of Ordered Indexing and Hashing, Bitmap Indices, Index Definition in SQL.

TRANSACTION MANAGEMENT Transactions : Transaction Concept, A Simple Transaction Model, Storage Structure, Transaction Atomicity and Durability, Transaction Isolation, Serializability, Transaction Isolation and Atomicity, Transaction Isolation Levels, Implementation of Isolation Levels, Transactions as SQL Statements. Unit V Concurrency Control : Lock-Based Protocols, Deadlock Handling, Multiple Granularity, Timestamp-Based Protocols, Validation-Based Protocols, Multi version Schemes, Snapshot Isolation, Insert Operations, Delete Operations, and Predicate Reads, Weak Levels of Consistency in Practice, Concurrency in Index Structures. Recovery System: Failure Classification, Storage, Recovery and Atomicity, Recovery Algorithm, Buffer Management, Failure with Loss of Nonvolatile Storage, Early Lock Release and Logical Undo Operations, ARIES, Remote Backup Systems.

TEXT BOOKS & OTHER REFERENCES Text Books 1. 1) Database System Concepts, Abraham Silberschatz, Henry F. Korth, S. Sudarshan, 6 th Edition, Tata Mc Graw-Hill. 2. 2) Database Management System, Raghu Rama Kirshna, Johannes Gchrke, TATA MC Graw Hill 3 rd Edition. Suggested / Reference Books 1. Data base Systems design, Implementation and Management Peter Rob & Carlos Coronel 7 th Edition. 2. 3 Fundamentals of Database Systems Elmasri Navrate Pearson Education. C.J. Date Introduction to Database Systems 8TH Edition, Addison-Wesley Longman, Inc.,2004 Websites References 1. 2. 3. http://en.wikipedia.org/wiki/database_normalization http://www.w3schools.com/sql/default.asp http://www.sql-tutorial.net/ 4. www.cs.iit.edu/~cs561/cs425/algebra/home.html 5. www.tutorialspoint.com/dbms/ 6. www.studytonight.com/dbms/ 7. www.dbms2.com 8. https://www.wiziq.com/tutorials/dbms 9. www.cramerz.com/database_concepts/dbms_and_rdbms 10. www.plsqlchallenge.com

12:20 1:00 LUNCH BREAK Time Table Room No: W.E.F: 15/12/2015 Class Hour Time MON 1 2 3 4 9:00-09:50 09.50 10:40 10:40 11:30 11:30 12: 20 5 6 7 1:00 1:50 1:50 2:40 2:40 3:30 TUE WED THU FRI SAT

PROGRAM EDUCATIONAL OBJECTIVES (PEO s) PEO1 PEO2 PEO3 PEO4 The Graduates are employable as software professionals in reputed industries. The Graduates analyze problems by applying the principles of computer science, mathematics and scientific investigation to design and implement industry accepted solutions using latest technologies. The Graduates work productively in supportive and leadership roles on multidisciplinary teams with effective communication and team work skills with high regard to legal and ethical responsibilities. The Graduates embrace lifelong learning to meet ever changing developments in computer science and Engineering. PROGRAM OUTCOMES (PO s) PO1 PO2 PO3 PO4 PO5 PO6 An ability to communicate effectively and work on multidisciplinary teams An ability to identify, formulate and solve computer system problems with professional and ethical responsibility. A recognition of the need for, and an ability to engage in life-long learning to use the latest techniques, skills and modern engineering tools The broad education necessary to understand the impact of engineering solutions in a global, economic, environmental and social context An ability to apply knowledge of mathematics, science, and computing to analyze, design and implement solutions to the realistic problems. An ability to apply suitable process with the understanding of software development practice.

Theory: Course Objectives: 1. To provide a sound introduction to Database management systems, Databases and its applications, 2. To familiarize the participant to give a good formal foundation on the relational model of data 3. To present SQL and procedural interfaces to SQL comprehensively 4. To give an introduction to systematic database design approaches conceptual design, logical design,schema refinement and physical design 5. To introduce the concepts of transactions and transaction processing and the issues and techniques relating to concurrency and recovery manager. Course Outcomes: CO 1 Develop the relational database tables and provide restricted access to different users of database and formulate the Complex SQL queries CO 2 Analyze Various Relational Formal Query Languages. CO 3 CO 4 CO 5 Implement Conceptual Database Design using Entity Relationship Model and Schema Refinement Process using various Normal Forms. To Analyze various file organization structures and use of suitable Indices and Hashing mechanisms for real time implementation. Analyze working principles of various protocols and algorithms implemented in specific DBMS Components Lab: Course Objectives: 1. To get exposure of various integrity constraints,clauses and its syntax for writing SQL queries. 2. To get exposure with programming constructs under PL/SQL. Course Outcomes: CO1 CO2 CO3 Use the SQL commands such as DDL, DML, DCL, TCL to create, manipulate, access data from database objects and providing authorization to access database by different users. To apply various integrity Constraints on the database tables for preserving the integrity of the database. Design and implement Pl/SQL programs which includes procedures, functions, cursor and triggers. MAPPING OF COURSE OUT COMES WITH PO s & PEO s Course Outcomes-CO S Programme Outcomes- PO s Programme Educational Objectives- PEO s CO 1 2&5 1,2 & 3 CO 2 1,2&5 1,2 & 3 CO 3 2,5&6 1,2,3 & 4 CO 4 5&6 1,2 & 4 CO 5 3&4 1,2 & 4

COURSE SCHEDULE Distribution of Hours Unit Wise Unit I II III IV Topic i. Introduction to Database System Concepts ii. Introduction to the Relation Models iii. Introduction to SQL i. Intermediate SQL ii. Advanced SQL iii. Formal Relational Query Languages i. Database Design and the E-R Model ii. Relational Database Design i. Storage and File Structure ii. Indexing and Hashing Book1 Chapters Book2 Total No. of Hours Ch1,2,3,4,5 Ch1,3 15 Ch 6,7,8 Ch 4,5 Ch9,10,11,12 Ch13,14,15 12 Ch2,15 11 Ch8.9,10 12 V i. Transactions ii. Concurrency Control iii. Recovery System Ch 16,17,18,19 Ch 18,19 15 Contact classes for Syllabus coverage 65

Tutorial Classes : 05 ; Online Quiz : 1 per unit Descriptive Tests : 02 (Before Mid Examination) Revision classes :1 per unit Number of Hours / lectures available in this Semester / Year 65 Lecture Plan S. No. Topic Date of Completion 1 2 3 Unit-1 Database-System Applications, Purpose of Database 01 Systems, View of Data, Database Languages, Relational Databases, Database Design, Data Storage and 01 Querying, Transaction Management, Database Architecture Data Mining and Information Retrieval, Spatial Databases 01 4 Database Users and Administrators, History of Database 01 Systems. 5 Structure of Relational Databases, Database Schema, 01 Keys 6 Tutorial class 01 7 Schema Diagrams, Relational Query Languages 01 Relational Operations, Overview of the SQL Query 01 8 Language 9 SQL Data Definition, Basic Structure of SQL Queries 01 10 Tutorial class 01 11 Additional Basic Operations, Null Values 01 12 Aggregate Functions, Set Operations 01 13 Nested Sub queries 01 14 Modification of the Database 01 Unit-2 16 Join Expressions 01 17 Views, Transactions, Integrity Constraints, 01 18 SQL Data Types and Schemas, Authorization. 01 19 Tutorial class 01 20 Functions and Procedures, 01 21 Triggers 01 22 Cursors 01 23 The Relational Algebra 01

24 The Tuple Relational Calculus, 01 25 The Domain Relational Calculus 01 26 Case Study-I 01 Unit-3 27 Overview of the Design Process 01 28 The Entity-Relationship Model, Constraints 01 29 Removing Redundant Attributes in Entity Sets 01 30 31 32 33 34 35 36 Entity-Relationship Diagrams, Reduction to Relational 01 Schemas Entity-Relationship Design Issues, Extended E-R 01 Features Tutorial class 01 Features of Good Relational Designs, Atomic Domains 01 and First Normal Form Decomposition Using Functional Dependencies, 01 Functional-Dependency Theory, Algorithms for Decomposition Decomposition Using Multivalued Dependencies, 01 More Normal Forms, Database-Design Process, Modeling Temporal Data. 37 Tutorial 01 Unit-4 38 Overview of Physical Storage Media 01 39 Magnetic Disk and Flash Storage 01 40 RAID, Tertiary Storage 01 41 File Organization, Organization of Records in Files 01 42 Data-Dictionary Storage, Database Buffer. 01 43 Tutorial class 01 Basic Concepts, Ordered Indices,B+-Tree Index Files, 01 44 B+-Tree Extensions 45 Multiple-Key Access, Static Hashing, Dynamic Hashing 01 Comparison of Ordered Indexing and Hashing, Bitmap 01 46 Indices, Index Definition in SQL. 47 Tutorial Class 01 Unit-5 48 Transaction Concept, A Simple Transaction Model 01 49 Storage Structure, Transaction Atomicity and Durability 01 50 Transaction Isolation, Serializability, Transaction 01 Isolation and Atomicity, 51 Transaction Isolation Levels, Implementation of Isolation 01 Levels 52 Tutorial class 01 53 Lock-Based Protocols, Deadlock Handling, Multiple Granularity 01 01

Timestamp-Based Protocols, Validation-Based Protocols, 01 54 Multiversion Schemes, Snapshot Isolation 55 Insert Operations, Delete Operations, and Predicate Reads 01 Weak Levels of Consistency in Practice, Concurrency in 01 56 Index Structures. 57 Case Study-II 01 58 Case Study-II 01 59 Failure Classification, Storage, Recovery and Atomicity,, 01 60 Recovery Algorithm, Buffer Management 01 61 Tutorial class 01 62 63 Failure with Loss of Nonvolatile Storage,Early Lock 01 Release and Logical Undo Operations ARIES, Remote Backup Systems. 01 64 Unit V Review 01

Date of Unit Completion & Remarks Unit 1 Date : / / Remarks: Unit 2 Date : / / Remarks: Unit 3 Date : / / Remarks: Unit 4 Date : / / Remarks:

Unit 5 Date : / / Remarks:

Unit Wise Assignments (With different Levels of thinking (Blooms Taxonomy)) Note: For every question please mention the level of Blooms taxonomy Unit 1 1. Explain the architecture of DBMS and levels of abstraction -L2 2. Compare and contrast conventional file processing with database system l3 3. Unit 2 Explain various languages (DDL,DML,DCL) and SQL operations(set and aggregate)- L3 1. Write short notes on joins,views, Authorization and Integrity Constraints-L2 2. Implement Various relational algebraic operations-l2 3. Differentiate the TRC and DRC.-L4 Unit 3 1. Explain complete ER Notations and its extended features with the neat sketch-l3 2. Explain various normal forms with examples-l3 Unit 4 1. Explain about RAID levels and indexing- and its types-l2 2. Contrast Static and Dynamic Hashing with examples-l3 Unit 5 1. Define Transaction states and its Isolation levels in detail-l2 2. Analyze the various Concurrency control protocols L4 3. Explain the ARIES and its related datastrctures-l2

Unit Wise Case Studies (With different Levels of thinking (Blooms Taxonomy)) Note: For every Case Study please mention the level of Blooms taxonomy Unit 1 1. 2. Develop a Database Design for Railway Reservation System- L3. Write a short notes Construct the B+ trees for the given-l3 2,3,7,9,11,13,17,19,21,23,27,29 of order 4.

6. Which one of the following is a set of one or more attributes taken collectively to uniquely identify a record? a) Candidate key b) Sub key c) Super key d) Foreign key Unit Wise Multiple Choice Questions for CRT & Competitive Examinations Unit---I 1. A relational database consists of a collection of a) Tables b) Fields c) Records d) Keys Answer:a 2. The term is used to refer to a row. a) Attribute b) Tuple c) Field d) Instance Answer:b. 3. For each attribute of a relation, there is a set of permitted values, called the of that attribute. a) Domain b) Relation c) Set d) Schema Answer:a. 4.Database, which is the logical design of the database, and the database,which is a snapshot of the data in the database at a given instant in time. a) Instance, Schema b) Relation, Schema c) Relation, Domain d) Schema, Instance Answer:d 5. The tuples of the relations can be of order. a) Any b) Same c) Sorted d) Constant Answer:a

Answer:c 7. The subset of super key is a candidate key under what condition? a) No proper subset is a super key b) All subsets are super keys c) Subset is a super key d) Each subset is a super key Answer:a 8. A attribute in a relation is a foreign key if the key from one relation is used as an attribute in that relation. a) Candidate b) Primary c) Super d) Sub Answer:b 9. A integrity constraint requires that the values appearing in specified attributes of any tuple in the referencing relation also appear in specified attributes of at least one tuple in the referenced relation. a) Referential b) Referencing c) Specific d) Primary Answer:a 10. Using which language can a user request information from a database? a) Query b) Relational c) Structural d) Compiler Answer:a. 11. Which one of the following is a procedural language? a) Domain relational calculus b) Tuple relational calculus c) Relational algebra d) Query language Answer:c 12. The operation allows the combining of two relations by merging pairs of tuples, one from each relation, into a single tuple. a) Select b) Join c) Union d) Intersection Answer:b 13. The result which operation contains all pairs of tuples from the two relations, regardless of whether their attribute values match. a) Join b) Cartesian product c) Intersection d) Set difference Answer:b 14.Which one of the following is used to define the structure of the relation,deleting relations and relating schemas? a) DML(Data Manipulation Langauge) b) DDL(Data Definition Langauge) c) Query d) Relational Schema Answer:b

15. Which one of the following provides the ability to query information from the database and to insert tuples into, delete tuples from, and modify tuples in the database? a) DML(Data Manipulation Langauge) b) DDL(Data Definition Langauge) c) Query d) Relational Schema Answer:a 16. Create table employee (name varchar,id integer) What type of statement is this? a) DML b) DDL c) View d) Integrity constraint Answer:b 17. Select * from employee What type of statement is this? a) DML b) DDL c) View d) Integrity constraint Answer:a 18. To remove a relation from an SQL database, we use the command. a) Delete b) Purge c) Remove d) Drop table Answer:d 19. Select * from employee where salary>10000 and dept_id=101; Which of the following fields are displayed as output? a) Salary, dept_id b) Employee c) Salary d) All the field of employee relation Answer:d 20. Select emp_name from department where dept_name like Computer Science ; Which one of the following has to be added into the blank to select the dept_name which has Computer Science as its ending string? a) % b) _ c) d) $ Answer:a 21. In SQL the spaces at the end of the string are removed by function. a) Upper b) String c) Trim d) Lower Answer:c 22. If we want to retain all duplicates, we must write in place of union. a) Union all b) Union some c) Intersect all d) Intersect some

Answer:a 23. joins are SQL server default a) Outer b) Inner c) Equi d) None of the mentioned Answer:b 24. In a employee table to include the attributes whose value always have some value which of the following constraint must be used? a) Null b) Not null c) Unique d) Distinct Answer:b 25. The primary key must be a) Unique b) Not null c) Both a and b d) Either a or b Answer:c 26. Select from instructor where dept name= Comp. Sci. ; Which of the following should be used to find the mean of the salary? a) Mean(salary) b) Avg(salary) c) Sum(salary) d) Count(salary) Answer:b 27. All aggregate functions except ignore null values in their input collection. a) Count(attribute) b) Count(*) c) Avg d) Sum Answer:b UNIT-----II 1. SQL applies predicates in the clause after groups have been formed, so aggregate functions may be used. a) Group by b) With c) Where d) Having Answer:b 2. Aggregate functions can be used in the select list or the clause of a select statement or subquery. They cannot be used in a clause. a) Where, having b) Having, where c) Group by, having d) Group by, where Answer:b 3. The keyword is used to access attributes of preceding tables or subqueries in the from clause. a) In b) Lateral

c) Having d) With Answer:b 4. Which of the following creates temporary relation for the query on which it is defined? a) With b) From c) Where d) Select Answer:a 5. With max_budget (value) as (select max(budget) from department) select budget from department, max_budget where department.budget = max budget.value; In the query given above which one of the following is a temporary relation? a) Budget b) Department c) Value d) Max_budget Answer:d 6.Which of the following is not a aggregate function? a) Avg b) Sum c) With d) Min View Answer Answer:c 7. The condition allows a general predicate over the relations being joined. a) On b) Using c) Set d) Where Answer:a 8. Which of the join operations do not preserve non matched tuples. a) Left outer join b) Right outer join c) Inner join d) Natural join Answer:c 9. What type of join is needed when you wish to include rows that do not have matching values? a) Equi-join b) Natural join c) Outer join d) All of the mentioned Answer:c 10. Which of the following creates a virtual relation for storing the query? a) Function b) View c) Procedure d) None of the mentioned Answer:b 11. In order to undo the work of transaction after last commit which one should be used? a) View

b) Commit c) Rollback d) Flashback Answer:c 12. A transaction completes its execution is said to be a) Committed b) Aborted c) Rolled back d) Failed Answer:a 13. Foreign key is the one in which the of one relation is referenced in another relation. a) Foreign key b) Primary key c) References d) Check constraint Answer:b 14. Domain constraints, functional dependency and referential integrity are special forms of. a) Foreign key b) Primary key c) Assertion d) Referential constraint Answer:c 15. An on an attribute of a relation is a data structure that allows the database system to find those tuples in the relation that have a specified value for that attribute efficiently, without scanning through all the tuples of the relation. a) Index b) Reference c) Assertion d) Timestamp Answer:a 16. Which of he following is used to input the entry and give the result in a variable in a procedure? a) Put and get b) Get and put c) Out and In d) In and out Answer:d 17. A is a special kind of a store procedure that executes in response to certain action on the table like insertion, deletion or updation of data. a) Procedures b) Triggers c) Functions d) None of the mentioned Answer:b 18. Trigger are supported in a) Delete b) Update c) Views d) All of the mentioned View Answer Answer:c

19. Ranking of queries is done by which of the following? a) Group by b) Order by c) Having d) Both a and b Answer:b 20. Which of the following is a fundamental operation in relational algebra? a) Set intersection b) Natural join c) Assignment d) None of the mentioned Answer:d UNIT----III 1.An is a set of entities of the same type that share the same properties, or attributes. a) Entity set b) Attribute set c) Relation set d) Entity model Answer:a 2. The function that an entity plays in a relationship is called that entity s. a) Participation b) Position c) Role d) Instance Answer:c 3., express the number of entities to which another entity can be associated via a relationship set. a) Mapping Cardinality b) Relational Cardinality c) Participation Constraints d) None of the mentioned Answer:a 4. Data integrity constraints are used to: a) Control who is allowed access to the data b) Ensure that duplicate records are not entered into the table c) Improve the quality of data entered for a specific property d) Prevent users from changing the values stored in the table Answer:c 5. Which one of the following uniquely identifies the elements in the relation? a) Secondary Key b) Primary key c) Foreign key d) Composite key Answer:b

6. is preferred method for enforcing data integrity a) Constraints b) Stored Procedure c) Triggers d) Cursors Answer:a 7. The entity relationship set is represented in E-R diagram as a) Double diamonds b) Undivided rectangles c) Dashed lines d) Diamond Answer:d 8. The Rectangles divided into two parts represents a) Entity set b) Relationship set c) Attributes of a relationship set d) Primary key Answer:a 9. An entity set that does not have sufficient attributes to form a primary key is termed a. a) Strong entity set b) Variant set c) Weak entity set d) Variable set Answer:c 10. Given the basic ER and relational models, which of the following is INCORRECT? a) An attribute of an entity can have more than one value b) An attribute of an entity can be composite c) In a row of a relational table, an attribute can have more than one value d) In a row of a relational table, an attribute can have exactly one value or a NULL value Answer:c 11. Which of the following indicates the maximum number of entities that can be involved in a relationship? a) Minimum cardinality b) Maximum cardinality c) ERD d) Greater Entity Count Answer:b 12. The entity set person is classified as student and employee.this process is called a) Generalization b) Specialization c) Inheritance d) Constraint generalization Answer:b 13. Functional dependencies are a generalization of a) Key dependencies

b) Relation dependencies c) Database dependencies d) None of the mentioned Answer:a 14. In the normal form, a composite attribute is converted to individual attributes. A) First B) Second C) Third D) Fourth Answer:a 15. A table on the many side of a one to many or many to many relationship must: a) Be in Second Normal Form (2NF) b) Be in Third Normal Form (3NF) c) Have a single attribute key d) Have a composite key Answer:d 16. Tables in second normal form (2NF): a) Eliminate all hidden dependencies b) Eliminate the possibility of a insertion anomalies c) Have a composite key d) Have all non key fields depend on the whole primary key Answer:a 17. A relation is in if an attribute of a composite key is dependent on an attribute of other composite key. a) 2NF b) 3NF c) BCNF d) 1NF Answer:b 18. If a multivalued dependency holds and is not implied by the corresponding functional dependency, it usually arises from one of the following sources. a) A many-to-many relationship set b) A multivalued attribute of an entity set c) A one-to-many relationship set d) Both a and b Answer:d UNIT----IV 1. Which of the following is a physical storage media? a) Tape Storage b) Optical Storage c) Flash memory d) All of the mentioned Answer:d 2. The is the fastest and most costly form of storage, which is relatively small; its use is managed by the computer system hardware. a) Cache b) Disk c) Main memory d) Flash memory Answer:a

3. There are record-once versions of compact disk and digital video disk, which can be written only once; such disks are also called disks. a) Write-once, read-many (WORM) b) CD-R c) DVD-W d) CD-ROM Answer:a 4. Tape storage is referred to as storage. a) Direct-access b) Random-access c) Sequential-access d) All of the mentioned Answer:c 5. A is the smallest unit of information that can be read from or written to the disk. a) Track b) Spindle c) Sector d) Platter Answer:c 6. The disk platters mounted on a spindle and the heads mounted on a disk arm are together known as. a) Read-disk assemblies b) Head disk assemblies c) Head-write assemblies d) Read-read assemblies Answer:b 7.. is the time from when a read or write request is issued to when data transfer begins. a) Access time b) Average seek time c) Seek time d) Rotational latency time Answer:a 8. Which level of RAID refers to disk mirroring with block striping? a) RAID level 1 b) RAID level 2 c) RAID level 0 d) RAID level 3 Answer:a 9. is popular for applications such as storage of log files in a database system, since it offers the best write performance. a) RAID level 1 b) RAID level 2 c) RAID level 0 d) RAID level 3 Answer:a

10. which increases the number of I/O operations needed to write a single logical block, pays a significant time penalty in terms of write performance. a) RAID level 1 b) RAID level 2 c) RAID level 5 d) RAID level 3 Answer:a 11. Tertiary storage is built with : a) a lot of money b) unremovable media c) removable media d) secondary storage Answer:c 12. The file organization which allows us to read records that would satisfy the join condition by using one block read is a) Heap file organization b) Sequential file organization c) Clustering file organization d) Hash file organization Answer: c 13. A relational database system needs to maintain data about the relations, such as the schema of the relations. This is called a) Metadata b) Catalog c) Log d) Dictionary Answer:a 14. The is that part of main memory available for storage of copies of disk blocks. a) Buffer b) Catalog c) Storage d) Secondary storage Answer:a 15. The purpose of an N-Ary association is: a) To capture a parent-child relationship b) To deal with one to many relationships c) To deal with relationships that involve more than two tables d) To represent an inheritance relationship Answer: c 16. Bitmap indices are a specialized type of index designed for easy querying on. a) Bit values b) Binary digits

c) Multiple keys d) Single keys Answer: c 17. A on the attribute A of relation r consists of one bitmap for each value that A can take. a) Bitmap index b) Bitmap c) Index d) Array Answer: a 18. Bitmaps can be combined with regular B+-tree indices for relations where a few attribute values are extremely common, and other values also occur, but much less frequently. a) Bitmap, B-tree b) Bitmap, B+tree c) B-tree, Bitmap d) B+tree, Bitmap Answer: b 19. In a B+-tree index, for each value we would normally maintain a list of all records with that value for the indexed attribute. a) Leaf b) Node c) Root d) Link Answer: a 20.How many types of indexes are there in sql server? a) 1 b) 2 c) 3 d) 4 Answer: b UNIT----V 1. A transaction is delimited by statements (or function calls) of the form. a) Begin transaction and end transaction b) Start transaction and stop transaction c) Get transaction and post transaction d) Read transaction and write transaction Answer:a 2. Identify the characteristics of transactions a) Atomicity b) Durability c) Isolation d) All of the mentioned

Answer:d 3. In SQL, which command is used to issue multiple CREATE TABLE, CREATE VIEW and GRANT statements in a single transaction? a) CREATE PACKAGE b) CREATE SCHEMA c) CREATE CLUSTER d) All of the mentioned Answer: b 4. The unit of storage that can store one are more records in a hash file organization are a) Buckets b) Disk pages c) Blocks d) Nodes Answer:a 5. A file system is software that enables multiple computers to share file storage while maintaining consistent space allocation and file content. a) Storage b) Tertiary c) Secondary d) Cluster Answer:d 6. If an transaction is performed in a database and committed, the changes are taken to the previous state of transaction by a) Flashback b) Rollback c) Both a and b d) Cannot be done Answer:d 7. means that data used during the execution of a transaction cannot be used by a second transaction until the first one is completed. a) Serializability b) Atomicity c) Isolation d) Time stamping Answer:c 8. Some of the utilities of DBMS are i) Loading ii) Backup iii) File organization iv) Process Organization a) i, ii, and iv only b) i, ii and iii only c) ii, iii and iv only d) All i, ii, iii, and iv Answer: b 9. In order to maintain transactional integrity and database consistency, what technology does a DBMS deploy? a) Triggers b) Pointers c) Locks

d) Cursors Answer:c 10. A lock that allows concurrent transactions to access different rows of the same table is known as a a) Database-level lock b) Table-level lock c) Page-level lock d) Row-level lock Answer:d 11. Which of the following are introduced to reduce the overheads caused by the log-based recovery? a) Checkpoints b) Indices c) Deadlocks d) Locks Answer:d 12. Which of the following protocols ensures conflict serializability and safety from deadlocks? a) Two-phase locking protocol b) Time-stamp ordering protocol c) Graph based protocol d) Both (a) and (b) above Answer:b 13. In a granularity hierarchy the highest level represents the a) Entire database b) Area c) File d) Record Answer: a 14. If a node is locked in, explicit locking is being done at a lower level of the tree, but with only shared-mode locks. a) Intention lock modes b) Intention-shared-exclusive mode c) Intention-exclusive (IX) mode d) Intention-shared (IS) mode Answer: a 15. denotes the largest timestamp of any transaction that executed write(q) successfully. a) W-timestamp(Q) b) R-timestamp(Q) c) RW-timestamp(Q) d) WR-timestamp(Q) Answer: a 16. ARIES uses a to identify log records, and stores it in database pages. a) Log sequence number b) Log number c) Lock number d) Sequence Answer: b

17. is used to minimize unnecessary redos during recovery. a) Dirty page table b) Page table c) Dirty redo d) All of the mentioned Answer: a 18. The remote backup site is sometimes also called the a) Primary Site b) Secondary Site c) Tertiary Site d) None of the mentioned Answer: b 19. Remote backup system must be with the primary site. a) Synchronised b) Separated c) Connected d) Detached but related Answer: a 20. The backup is taken by a) Erasing all previous records b) Entering the new records c) Sending all log records from primary site to the remote backup site d) Sending selected records from primary site to the remote backup site Answer: a

University Question Papers Code No: R09220502 R09 Set No. 2 II B.Tech II Semester Examinations,APRIL 2011 DATA BASE MANAGEMENT SYSTEMS Common to ME, IT, MECT, AME, CSE, ECE Time: 3 hours Max Marks: 75 Answer any FIVE Questions All Questions carry equal marks????? 1. (a) Brie y explain the Database Design process. (b) De ne these terms: Entity, Entity set, Attribute, Key. [7+8] 2. Explain schema re nement in Database Design? [15] 3. (a) Write a note on DBMS? Explain Database System Applications. (b) What is a Data Model? Explain ER data model. [7+8] 4. During its execution, a transaction passes through several states, until it nally commits or aborts. List all possible sequences of states through which a transaction may pass. Explain why each state transition may occur? [15] 5. (a) How is Data organized in Tree based index? (b) When would users use a Tree based index? [7+8] 6. Explain ARIES. [15] 7. (a) Consider the following Relations Student (snum: integer, sname: string, major: string, level: string, age: integer) Class (name: string, meets at: time, room: string, d: integer) Enrolled (snum: integer, cname: string) Faculty ( d: integer, fname: string, deptid: integer) Write the following queries in SQL. i. Find the names of students not enrolled in any class. ii. Find the names of students enrolled in the maximum number of classes. iii. Print the level and the average age of students for that level, for each level. iv. Print the level and the average age of the students for that level, for all levels except JR. (b) Explain following in brief i. Triggers ii. Assertions [11+4]

8. Consider the following Schema: Suppliers (sid : integer, sname: string, address: string) Parts (pid : integer, pname: string, color: string) www.jntuworld.com

www.jntuworld.com Code No: R09220502 R09 Set No. 2 Catalog (sid : integer; pid : integer, cost: real) The key elds are underlined. The catalog relation lists the price changes for parts by supplies. Write the following Queries in Relational Algebra and tuple relational calculus. (a) Find the sids of suppliees who supply some red part and some green part (b) Find the sids of suppliees who supply every part (c) Find the sids of suppliees who supply every red or green part (d) Find the pids of parts supplied by at least two di erent suppliees. [15]????? www.jntuworld.com

www.jntuworld.com Code No: R09220502 R09 Set No. 4 II B.Tech II Semester Examinations,APRIL 2011 DATA BASE MANAGEMENT SYSTEMS Common to ME, IT, MECT, AME, CSE, ECE Time: 3 hours Max Marks: 75 Answer any FIVE Questions All Questions carry equal marks????? 1. (a) Explain how to di erentiate attributes in Entity set? (b) Explain all the functional dependencies in Entity sets? [7+8] 2. (a) Discuss about DDL and DML. (b) What are ve main functions of Database Administrator? Explain [8+7] 3. (a) Construct an ER diagram for a bank Database. Bank maintains data about customers, their loans, their deposits, lockers. Determine the entities and relationships. (b) De ne the terms: Entity Set, Role, Relationship set, Aggregation. [7+8] 4. (a) Explain dynamic Data structure? (b) Explain over ow of pages? [7+8] 5. (a) Explain about the basic form of a SQL queries. (b) Write the following queries in SQL for the following schema. Sailors (sid: integer, sname: string, rating: integer, age: real) Boats (bid: integer, bname: string, color: string) Reserves (sid: integer, bid: integer, day: date) i. Compute increments for the ratings of persons who have sailed two different boats on the same day. ii. Find the ages of sailors whose names begins and ends with B and has at least three characters. iii. Find the colors of boats reserved by Raghu. iv. Find the sids of all sailors who have reserved red boats but not green boats. [7+8] 6. (a) De ne the divisible operation in terms of the basic relational algebra opera-tions. Describe a typical query that calls for division. Unlike join, the division operation is not given special treatment in database systems. Explain why. (b) Database Systems use some variant of Relational Algebra to represent query evaluation plans. Explain why Algebra is suitable for this purpose. [7+8] 7. (a) What is Thomas write rule? (b) Explain the time-stamp ordering protocol? [7+8] 8. Explain advanced recovery Techniques? [15]????? www.jntuworld.com

www.jntuworld.com Code No: R09220502 R09 Set No. 1 II B.Tech II Semester Examinations,APRIL 2011 DATA BASE MANAGEMENT SYSTEMS Common to ME, IT, MECT, AME, CSE, ECE Time: 3 hours Max Marks: 75 Answer any FIVE Questions All Questions carry equal marks????? 1. (a) Give a note on storage manager component of database system structure. (b) Make a comparison between Database system and File system. [7+8] 2. (a) How the Data is stored in External Storage? (b) Explain le organization & indexing? [7+8] 3. (a) Construct an ER diagram for university registrar's o ce. The o ce maintains data about each class, including the instructor, the enrollment and the time and place of the class meetings. For each student class pair a grade is recorded. Determine the entities and relationships. (b) What is the composite attribute? How to model it in the ER diagram? Explain with an example. [7+8] 4. Explain the Di erence between three storage types, Volatile, Non-Volatile and Stable in terms of I/O cost. [15] 5. (a) Discuss about Tuple Relational Calculus in detail. (b) Write the following queries in Tuple Relational Calculus for following Schema. Sailors (sid: integer, sname: string, rating: integer, age: real) Boats (bid: integer, bname: string, color: string) Reserves (sid: integer, bid: integer, day: date) i. Find the names of sailors who have reserved a red boat ii. Find the names of sailors who have reserved at least one boat iii. Find the names of sailors who have reserved at least two boats iv. Find the names of sailors who have reserved all boats. [7+8] 6. (a) Explain constraints on an Entity set. (b) Explain constraints on a Relationship set. [7+8] 7. (a) Write the following queries in SQL using Nested queries concept for following Schema. Sailors (sid: integer, sname: string, rating: integer, age: real) Boats (bid: integer, bname: string, color: string) Reserves (sid: integer, bid: integer, day: date) i. Find the names of sailors who have reserved both red and green boat ii. Find the names of sailors who have reserved all boats www.jntuworld.com

www.jntuworld.com Code No: R09220502 R09 Set No. 1 iii. Find the names of sailors who have not reserved red boat iv. Find sailors whose rating is better than some sailor called raghu. (b) What is a correlated nested query? Explain with an example. [11+4] 8. Consider the following two transactions: T 1 : read(a); read(b); if A=0 then B:= B + 1; write(b). T 2 : read(b); read(a); if B=0 then A:= A + 1; write(a). Let the consistency requirement be A=0 V B=0, with A=B=0 the initial values. (a) Show that every serial execution involving these two transactions preserves the consistency of the Database? (b) Show a concurrent execution of T 1 and T 2 that produces a non serializable Schedule? (c) Is there a concurrent execution of T 1 and T 2 that produces a serializable Schedule? [5+5+5]????? www.jntuworld.com

www.jntuworld.com Code No: R09220502 R09 Set No. 3 II B.Tech II Semester Examinations,APRIL 2011 DATA BASE MANAGEMENT SYSTEMS Common to ME, IT, MECT, AME, CSE, ECE Time: 3 hours Max Marks: 75 Answer any FIVE Questions All Questions carry equal marks????? 1. (a) Explain covering constraints & overlap constraints. (b) Give a detail note on weak entity set. [7+8] 2. (a) Explain functional dependency with an example? (b) Compare Third NF and BCNF, explain with examples? [11+4] 3. (a) What is the relationship betweens les & indexes? (b) What is the search key for an index? (c) What is Data entry in an index? [7+4+4] 4. (a) Explain the Database users and user interfaces. (b) Discuss the function of Database Administrator. [9+6] 5. (a) Discuss about joins in Relational Algebra with examples. (b) Explain about set operations in Relational Algebra with examples. [7+8] 6. Explain shadow-copy technique for Atomicity and Durability? [15] 7. (a) Consider the following Relations Student (snum: integer, sname: string, major: string, level: string, age: integer) Class (name: string, meets at: time, room: string, d: integer) Enrolled (snum: integer, cname: string) Faculty ( d: integer, fname: string, deptid: integer) Write the following queries in SQL. i. Find the names of all juniors (level = JR) who are enrolled in a class taught by I. teach. ii. Find the age of the oldest student who is either a History major or enrolled in a course taught by I. teach. iii. Find the names of all classes that either meet in a room R128 or have

ve or more students enrolled. iv. Find the number of all students who are enrolled in two classes that meet at the same time. (b) What is a trigger and what are its 3 parts. Explain in detail. [11+4] 8. Stable Storage cant be Implemented, Explain why it can't be? [15] 2????? 6

3 Tutorial Sheet Topics Revised Date: Unit-I Quick Test Topics Date: Case Study Discussed Date:

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8 TOPICS BEYOND SYLLABUS 1) Introduction to Oracle Reports 9i and Oracle forms 9i 2) Query Optimization. Add-on Programmes: 1. My Sql Certification through FOSS Programme 2 3 4 Guest Lectures: 1. Workshop on IBM DB2 2. 3. 4. Unit Wise PPT s:

9 Unit Wise lecture Notes: What is a Database? To find out what database is, we have to start from data, which is the basic building block of any DBMS. Data: Facts, figures, statistics etc. having no particular meaning (e.g. 1, ABC, 19 etc). Record: Collection of related data items, e.g. in the above example the three data items had no meaning. But if we organize them in the following way, then they collectively represent meaningful information. Roll Name Age 1 ABC 19 Table or Relation: Collection of related records. Roll Name Age 1 ABC 19 2 DEF 22 3 XYZ 28 The columns of this relation are called Fields, Attributes or Domains. The rows are called Tuples or Records. Database: Collection of related relations. Consider the following collection of tables: T1 Roll Name Age 1 ABC 19 2 DEF 22 3 XYZ 28 Roll T2 Address 1 KOL 2 DEL 3 MUM

10 T3 Roll Year 1 I 2 II 3 I T4 Year I II Hostel H1 H2 We now have a collection of 4 tables. They can be called a related collection because we can clearly find out that there are some common attributes existing in a selected pair of tables. Because of these common attributes we may combine the data of two or more tables together to find out the complete details of a student. Questions like Which hostel does the youngest student live in? can be answered now, although Age and Hostelattributes are in different tables. In a database, data is organized strictly in row and column format. The rows are calledtuple or Record. The data items within one row may belong to different data types. On the other hand, the columns are often called Domain or Attribute. All the data items within a single attribute are of the same data type. What is Management System? A management system is a set of rules and procedures which help us to create organize and manipulate the database. It also helps us to add, modify delete data items in the database. The management system can be either manual or computerized. The management system is important because without the existence of some kind of rules and regulations it is not possible to maintain the database. We have to select the particular attributes which should be included in a particular table; the common attributes to create relationship between two tables; if a new record has to be inserted or deleted then which tables should have to be handled etc. These issues must be resolved by having some kind of rules to follow in order to maintain the integrity of the database. Views of Data We know that the same thing, if viewed from different angles produces difference sights. Likewise, the database that we have created already can have different aspects to reveal if seen from different levels of abstraction. The term Abstraction is very important here. Generally it means the amount of detail you want to hide. Any entity can be seen from different perspectives and levels of complexity to make it a reveal its current amount of abstraction. Let us illustrate by a simple example. A computer reveals the minimum of its internal details, when seen from outside. We do not know what parts it is built with. This is the highest level of abstraction, meaning very few details are visible. If we open the computer case and look inside at the hard disc, motherboard, CD drive, CPU and RAM, we are in middle level

of abstraction. If we move on to open the hard disc and examine its tracks, sectors and read-write heads, we are at the lowest level of abstraction, where no details are invisible. In the same manner, the database can also be viewed from different levels of abstraction to reveal different levels of details. From a bottom-up manner, we may find that there are three levels of abstraction or views in the database. We discuss them here. 11 The word schema means arrangement how we want to arrange things that we have to store. The diagram above shows the three different schemas used in DBMS, seen from different levels of abstraction. The lowest level, called the Internal or Physical schema, deals with the description of how raw data items (like 1, ABC, KOL, H2 etc.) are stored in the physical storage (Hard Disc, CD, Tape Drive etc.). It also describes the data type of these data items, the size of the items in the storage media, the location (physical address) of the items in the storage device and so on. This schema is useful for database application developers and database administrator. The middle level is known as the Conceptual or Logical Schema, and deals with the structure of the entire database. Please note that at this level we are not interested with the raw data items anymore, we are interested with the structure of the database. This means we want to know the information about the attributes of each table, the common attributes in different tables that help them to be combined, what kind of data can be input into these attributes, and so on. Conceptual or Logical schema is very useful for database administrators whose responsibility is to maintain the entire database. The highest level of abstraction is the External or View Schema. This is targeted for the end users. Now, an end user does not need to know everything about the structure of the entire database, rather than the amount of details he/she needs to work with. We may not want the end user to become confused with astounding amount of details by allowing him/her to have a look at the entire database, or we may also not allow this for the purpose of security, where sensitive information must remain hidden from unwanted persons. The database administrator may want to create custom made tables, keeping in mind the specific kind of need for each user. These tables are also known as virtual tables, because they have no separate physical existence. They are crated dynamically for the users at runtime. Say for example, in our sample database we have created earlier, we have a special officer whose responsibility is to keep in touch with the parents of any under aged student living in the hostels. That officer does not need to know every detail except the Roll, Name,

Addresss and Age. The database administrator may create a virtual table with only these four attributes, only for the use of this officer. Data Independence This brings us to our next topic: data independence. It is the property of the database which tries to ensure that if we make any change in any level of schema of the database, the schema immediately above it would require minimal or no need of change. What does this mean? We know that in a building, each floor stands on the floor below it. If we change the design of any one floor, e.g. extending the width of a room by demolishing the western wall of that room, it is likely that the design in the above floors will have to be changed also. As a result, one change needed in one particular floor would mean continuing to change the design of each floor until we reach the top floor, with an increase in the time, cost and labour. Would not life be easy if the change could be contained in one floor only? Data independence is the answer for this. It removes the need for additional amount of work needed in adopting the single change into all the levels above. Data independence can be classified into the following two types: Physical Data Independence: This means that for any change made in the physical schema, the need to change the logical schema is minimal. This is practically easier to achieve. Let us explain with an example. Say, you have bought an Audio CD of a recently released film and one of your friends has bought an Audio Cassette of the same film. If we consider the physical schema, they are entirely different. The first is digital recording on an optical media, where random access is possible. The second one is magnetic recording on a magnetic media, strictly sequential access. However, how this change is reflected in the logical schema is very interesting. For music tracks, the logical schema for both the CD and the Cassette is the title card imprinted on their back. We have information like Track no, Name of the Song, Name of the Artist and Duration of the Track, things which are identical for both the CD and the Cassette. We can clearly say that we have achieved the physical data independence here. Logical Data Independence: This means that for any change made in the logical schema, the need to change the external schema is minimal. As we shall see, this is a little difficult to achieve. Let us explain with an example. Suppose the CD you have bought contains 6 songs, and some of your friends are interested in copying some of those songs (which they like in the film) into their favorite collection. One friend wants the songs 1, 2, 4, 5, 6, another wants 1, 3, 4, 5 and another wants 1, 2, 3, 6. Each of these collections can be compared to a view schema for that friend. Now by some mistake, a scratch has appeared in the CD and you cannot extract the song 3. Obviously, you will have to ask the friends who have song 3 in their proposed collection to alter their view by deleting song 3 from their proposed collection as well. Database Administrator The Database Administrator, better known as DBA, is the person (or a group of persons) responsible for the well being of the database management system. S/he has the flowing functions and responsibilities regarding database management: Definition of the schema, the architecture of the three levels of the data abstraction, data independence. Modification of the defined schema as and when required. Definition of the storage structure i.e. and access method of the data stored i.e. sequential, indexed or direct. 12