Size: px
Start display at page:

Download ""

Transcription

1

2

3

4

5

6

7

8

9

10

11

12

13

14 Q.2 e) Time stamping protocol for concurrrency control Time stamping ids a concurrency protocol in which the fundamental goal is to order transactions globally in such a way that older transactions get priority in the event of a conflict.

15 In this method, if a transaction attempts to read or write a data item, then a read or write operation is allowed only if the last updated on that data item was carried out by an older transaction. Otherwise the transaction, requesting the read or write is restarted and given a new timestamp. The restarted transaction is assigned a new timestamp to prevent it from continuously aborting and restarting. In this method, sequence of transaction is selected in advance by using time stamping concept. We associate a unique, fixed non-decreasing numbers called the timestamp to each transaction in the system. This number can be the system clock value, i.e. when the transaction enters the system the current value of the clock is assigned to that transaction as the timestamp value. We can also use a logical number that is incremented after a new transaction enters the system. A transaction with a smaller timestamp value is considered to be an adder transaction than another transaction with a larger time stamp value. In other words, if a transaction T1 has been assigned a timestamp S1 and a new transaction T2 enters the system with a time stamp value S2 then S1<S2 and system will allow the transaction T1 to run first followed by the transaction T2. If any conflict is found between transaction using timestamp based system, one of the conflicting transaction is rolled back. There are two types of timestamps: W-time stamp (Q): Denotes the largest time stamp of any transaction that executed write(q) successfully. R-Time stamp (Q): Denotes the largest time stamp of any transaction that executed read(q) successfully. Concurrency Control: Multi version Scheme Multiversion schemes keep old versions of data item to increase concurrency. Multiversion Timestamp Ordering Multiversion Two-Phase Locking Each successful write results in the creation of a new version of the data item written. Use timestamps to label versions. When a read(x) operation is issued, select an appropriate version of X based on the timestamp of the transaction, and return the value of the selected version. reads never have to wait as an appropriate version is returned immediately. Section C Answer. 3 a) Redundancy - Repetitive storage of data leading to possible multiple versions and/or ill utilisation of data storage capacity. Inconsistency - Failure to adhere to standardized storage of data; usage of varying formats, non-confirmation to standardized/defined methods to store similar/related data. File Systems Applications are developed on the fly Redundant information Inconsistency:

16 Answer 3 b) File Systems Data representation Each file has its own logical format File organisation varies with applications Programs access files in accordance with their access methods and logical format new format implies creating new file & accessing existing ones

17 Data Bases Remove redundancy: centralize all data, represent in exactly one place Provide global logical view Separate logical view from physical to allow customized logical views Enable sharing: all applications may run concurrently A data base is a central pool of data sharable among its many users loss of individual control of data response times in accordance with organisation needs Some main differences between a database management system and a file-processing system are: Both systems contain a collection of data and a set of programs which access that data. A database management system coordinates both the physical and the logical access to the data, whereas a file-processing system coordinates only the physical access. A databasemanagement system reduces the amount of data duplication by ensuring that a physical piece of data is available to all programs authorized to have access to it,whereas data written by one programin a file-processing system may not be readable by another program. A database management system is designed to allow flexible access to data (i.e., queries), whereas a file-processing system is designed to allow predetermined access to data (i.e., compiled programs). A database management system is designed to coordinate multiple users accessing the same data at the same time. A file-processing systemis usually designed to allow one or more programs to access different data files at the same time. In a fileprocessing system, a file can be accessed by two programs concurrently only if both programs have read-only access to the file. Answer 3 C)

18 Three level Architecture (ANSI/SPARC) File System is very low level record but no logical relationship, only physical position Operation in physical terms, not logical Define a logical level for a logical model A model is a set of concepts, relationships between these, and constraints DBA External layer Logical layer Internal/physical layer Define a user view of the model Data Base Views The Enterprise View The User s The User s The Logical Database The Physical Database

19 Database Roles Enterprise Manager:Ensures organisation mirroring DB A External layer Logical layer Applications Manager: For specific logical views Physical layer Answer 4 a) The relational algebra is a procedural query language. It consists of a set of operations that take one or two relation as input and produce a new relation as output. Relational algebra is the basic set of operations for the relational model These operations enable a user to specify basic retrieval requests (or queries) The result of an operation is a new relation, which may have been formed from one or more input relations Relational Algebra consists of several groups of operations Unary Relational Operations SELECT (symbol: (sigma)) PROJECT (symbol: (pi)) RENAME (symbol: (rho)) Relational Algebra Operations From Set Theory UNION ( ), INTERSECTION ( ), DIFFERENCE (or MINUS, ) CARTESIAN PRODUCT ( x ) Binary Relational Operations JOIN (several variations of JOIN exist) DIVISION Additional Relational Operations OUTER JOINS, OUTER UNION AGGREGATE FUNCTIONS (These compute summary of information: for example, SUM, COUNT, AVG, MIN, MAX) The Relational Calculus A relational calculus expression creates a new relation, which is specified in terms of variables that range over rows of the stored database relations (in tuple calculus) or over columns of the stored relations (in domain calculus).

20 In a calculus expression, there is no order of operations to specify how to retrieve the query result a calculus expression specifies only what information the result should contain. This is the main distinguishing feature between relational algebra and relational calculus. Relational calculus is considered to be a nonprocedural language. This differs from relational algebra, where we must write a sequence of operations to specify a retrieval request; hence relational algebra can be considered as a procedural way of stating a query. Answer. 4 b) Trigger : A series of PL/SQL statements attached to a database table that execute whenever a triggering event (select, update, insert, delete) occurs. Application/Database Triggers : PL/SQL block that is associated with an application even event/database table and is fired automatically A trigger is a PL/SQL code block attached to a database table. It is executed by an event (INSERT, UPDATE, DELETE) associated with that table. Triggers are thus implicitly invoked by DML commands. Triggers are stored as text and compiled at execution time, because of this it is wise not to include much code in them but to call out to previously stored procedures or packages as this will greatly improve performance. Remember that triggers may be executed thousands of times for a large update - they can seriously affect SQL execution performance. Answer 4 c) Example of Trigger

21 Example of Different Joins (Cross, Natural, Inner, Outer) Assume 2 tables A and B has values with the 1 st column of each table as the common column, in the following: Table A: 2 3 Table B: 1 A I 2 B II 4 D IV 1. Cross Join: append at the end of every row of Table A by every row of Table B. SQL command: select * from A cross join B; Result: 2 1 A I 2 2 B II 2 4 D IV 3 1 A I 3 2 B II 3 4 D IV 2. Natural Join: after Cross Join, pick up only rows with the same (or matching) common column values. Show the common column value only once SQL command: select * from A natural join B; Result: 2 B II 3. Inner Join: after Cross Join, pick up only rows with the same (or matching) common column values. However, show the common column values for both tables. You must specify the common column(s). SQL command: select * from A inner join B On A.commoncolumn=B.commoncolumn; Result: 2 2 B II Comparison of external join and Natural Join: Natural Join is special kind of syntax. Unlike explicit inner and outer join syntax. Natural join syntax has implicit join condition. It is both its strength and weaknessstrength because one can write a bit less words, weakness because it is quite dangerous and unprotected to structure changes of tables.

22 Assume 2 tables A and B has values with the 1 st column of each table as the common column, in the following: Table A: 2 3 Table B: 1 A I 2 B II 4 D IV Concrete Example: Table Course: NAME COURSE NUMBER John ITEC 122 Cindy ITEC 120 Table Student: NAME PHONE GPA NUMBER John David Cindy Cross Join: append at the end of every row of Table A by every row of Table B. SQL command: select * from A cross join B; Result: 2 1 A I 2 2 B II 2 4 D IV 3 1 A I 3 2 B II 3 4 D IV 2. Natural Join: after Cross Join, pick up only rows with the same (or matching) common column values. Show the common column value only once. Must have common names between 2 tables. SQL command: select * from A natural join B; Result: 2 B II

23 Concrete Example: SQL: select * from Course natural join Student; Result: NAME COURSE NUMBER PHONE NUMBER GPA John ITEC Cindy ITEC Inner Join: after Cross Join, pick up only rows with the same (or matching) common column values. However, show the common matched column values for both tables. You must specify the common column(s). SQL command: select * from A inner join B On A.commoncolumn=B.commoncolumn; Result: 2 2 B II Concrete Example: SQL: select * from Course inner join Student On Course.Name= Student. Name; Result: NAME COURSE NUMBER NAME PHONE NUMBER GPA John ITEC 122 John Cindy ITEC 120 Cindy Outer Join: (1) Left Outer Join: after Inner Join, add rows of the left Table (A) which is non-matching common column values from row of Cross Join with all fields of Table B blanked. You must specify the common column(s). SQL command: select * from A left outer join B On A.commoncolumn=B.commoncolumn; Result: 2 2 B II 3 Concrete Example: If you want to find out who are new in the school (who don t have any GPA yet) SQL: select * from Course left outer join Student On Course.Name= Student. Name; Result: NAME COURSE NUMBER PHONE NUMBER GPA John ITEC

24 Cindy ITEC (2) Right Outer Join: after Inner Join, add rows of the right Table (B) which is non-matching common column values from row of Cross Join with all fields of Table A blanked. You must specify the common column(s). SQL command: select * from A right outer join B On A.commoncolumn=B.commoncolumn; Result: 2 2 B II 1 A I 4 D IV Concrete Example: If you want to find out students who are not taking any class SQL: select * from Course right outer join Student On Course.Name= Student. Name; Result: NAME COURSE NUMBER PHONE NUMBER GPA John ITEC David Cindy ITEC (3) Full Outer Join: after Inner Join, add rows of the left Table (A) and the right Table (B) which are non-matching common column values from row of Cross Join with all fields of the other Table blanked. You must specify the common column(s). SQL command: select * from A full join B On A.commoncolumn=B.commoncolumn; Result: 2 2 B II 3 1 A I 4 D IV Answer 5 a) Armstrong s axioms Reflexivity rule If A is a set of attributes and B A A B Augmentation rule If A B holds and C is a set of attributes CA CB

25 Transitivity rule If A B holds and B C holds A C These axioms are sound and complete they generate all other functional dependencies for a given set F of functional dependencies. Answer.5 b) Need of Normalization Result of E-R analysis need further refinement Appropriate decomposition can solve problems The underlying theory is referred to as normalization theory and is based on functional dependencies (and other kinds, like multi-valued dependencies) Normalization is a design technique that is widely used as a guide in designing relational databases. Normalization is essentially a two step process 1) that puts data into tabular form by removing repeating groups and 2) then removes duplicated data from the relational tables. Normalization theory is based on the concepts of normal forms. A relational table is said to be a particular normal form if it satisfied a certain set of constraints. Normalization is a process for assigning attributes to entities. It reduces data redundancies and helps eliminate the data anomalies. Normalization is a process of refining table structures into a proper state so that they can store data as efficiently as possible. Normalization works through a series of stages called normal forms: o First normal form (1NF) o Second normal form (2NF) o Third normal form (3NF) o Fourth normal form (4NF) The highest level of normalization is not always desirable. Answer.5 c)

26 Third Normal Form(3NF) Codd s Definition A relation is in 3NF if it satisfies 2NF and no nonprime attribute of R is transitively dependent on the primary key 3NF Decomposition Algorithm If A B and B C in R then create R1(A,B), R2 (B,C) Equivalently, A relation is in 3 NF if for every functional dependency X A, one of the following statements is true: i) it is a trivial FD X is a superkey A is a prime attribute Consider a relation Stdinf (Name, Phoneno, Course, Major, Prof., Grade, Major-Elective) with following FD s Name Course Phoneno Major Prof.. Grade Major-Elective The key of the relation is {Name Course} The partial dependencies are caused by Name Phoneno Name Major and Course Prof. The only transitive dependency is Name Major, Major Major-Elective.

27 Consider a relation Stdinf (Name, Phoneno, Course, Major, Prof., Grade, Major-Elective) with following FD s Name Course Phoneno Major Prof.. Grade Major-Elective The key of the relation is {Name Course} The partial dependencies are caused by Name Phoneno Name Major and Course Prof. The only transitive dependency is Name Major, Major Major-Elective. 3NF Decomposition: R1-1(Name,Phoneno,Major) R1-2(Major, Major-Elective) R2(Course, Prof.) R3(Name,Course,Grade) BCNF Need For BCNF arises when X A and A B where B is a subset of X Student (Name, Course, Teacher) and Name Course Teacher Note: Name, Course is the primary key of Student Name Course Teacher A C1 T1 B C1 T1 C C2 T2

28 A relation R is in BCNF if it is in 1NF and for every collection C of fields, if any field not in C is functionally dependent on C, then C R A relation is in BCNF if whenever a functional dependency X A holds then, either i) X is a super key of R, or ii) X A is trivial (A is subset of X) Difference with 3NF: A cannot be a prime attribute Lossless BCNF Decomposition For R(A,B,C) if A,B C and C B, decompose R into R1(C,B) and R2 (R - B) Note: Dependency Non-preserving Comparison of BCNF and 3NF Every BCNF relation is in 3 NF, but not vice versa. 3NF is Lossy and Dependency preserving. BCNF is Lossless and is not necessarily Dependency preserving Answer 6 a) Deadlock: when each of two transactions is waiting for the other to release an item. Approaches for solution: o deadlock prevention protocol: every transaction must lock all items it needs in advance o deadlock detection (if the transaction load is light or transactions are short and lock only a few items):

29 Livelock: a transaction cannot proceed for an indefinite period of time while other transactions in the system continue normally. o Solution: fair waiting schemes (i.e. first-come-first-served) The deadlock is different from starvation. Starvation is the problem that occurs when a process is waiting for a resource that is allocated to other processes, released, and then allocated again to some process other than the one that is starving. Answer 6 b) Purpose of Database Recovery To bring the database into the last consistent state, which existed prior to the failure. To preserve transaction properties (Atomicity, Consistency, Isolation and Durability). Example: If the system crashes before a fund transfer transaction completes its execution, then either one or both accounts may have incorrect value. Thus, the database must be restored to the state before the transaction modified any of the accounts. Transaction Roll-back (Undo) and Roll-Forward (Redo) To maintain atomicity, a transaction s operations are redone or undone. Undo: Restore all BFIMs on to disk (Remove all AFIMs). Redo: Restore all AFIMs on to disk. Database recovery is achieved either by performing only Undos or only Redos or by a combination of the two. These operations are recorded in the log as they happen. Answer 7a) ACID Properties To preserve integrity of data, the database system must ensure: 1. Atomicity. Either all operations of the transaction are properly reflected in the database or none are. 2. Consistency. Execution of a transaction in isolation preserves the consistency of the database. 3. Isolation. Although multiple transactions may execute concurrently, each transaction must be unaware of other concurrently executing transactions. Intermediate transaction results must be hidden from other concurrently executed transactions. a. That is, for every pair of transactions Ti and Tj, it appears to Ti that either Tj, finished execution before Ti started, or Tj started execution after Ti finished. 4. Durability. After a transaction completes successfully, the changes it has made to the database persist, even if there are system failures. Answer 7 b) Validation-Based Protocol

30 Execution of transaction Ti is done in three phases. 1. Read and execution phase: Transaction Ti writes only to temporary local variables 2. Validation phase: Transaction Ti performs a ``validation test'' to determine if local variables can be written without violating serializability. 3. Write phase: If Ti is validated, the updates are applied to the database; otherwise, Ti is rolled back. The three phases of concurrently executing transactions can be interleaved, but each transaction must go through the three phases in that order. Assume for simplicity that the validation and write phase occur together, atomically and serially I.e., only one transaction executes validation/write at a time. Also called as optimistic concurrency control since transaction executes fully in the hope that all will go well during validation Answer 7 c) Multiple Granularity Locking Scheme Transaction Ti can lock a node Q, using the following rules: 1. The lock compatibility matrix must be observed. 2. The root of the tree must be locked first, and may be locked in any mode. 3. A node Q can be locked by Ti in S or IS mode only if the parent of Q is currently locked by Ti in either IX or IS mode. 4. A node Q can be locked by Ti in X, SIX, or IX mode only if the parent of Q is currently locked by Ti in either IX or SIX mode. 5. Ti can lock a node only if it has not previously unlocked any node (that is, Ti is two-phase). 6. Ti can unlock a node Q only if none of the children of Q are currently locked by Ti. Observe that locks are acquired in root-to-leaf order, whereas they are released in leaf-to-root order.

ss A good decomposition must be lossless and dependency preserving 1. Lossless-Join Decomposition Exactly the original information can be recovered by joining 2. Non-Lossless-Join or Lossy Decomposition

More information

Database Management Systems Paper Solution

Database Management Systems Paper Solution Database Management Systems Paper Solution Following questions have been asked in GATE CS exam. 1. Given the relations employee (name, salary, deptno) and department (deptno, deptname, address) Which of

More information

Graph-based protocols are an alternative to two-phase locking Impose a partial ordering on the set D = {d 1, d 2,..., d h } of all data items.

Graph-based protocols are an alternative to two-phase locking Impose a partial ordering on the set D = {d 1, d 2,..., d h } of all data items. Graph-based protocols are an alternative to two-phase locking Impose a partial ordering on the set D = {d 1, d 2,..., d h } of all data items. If d i d j then any transaction accessing both d i and d j

More information

DATABASE MANAGEMENT SYSTEMS

DATABASE MANAGEMENT SYSTEMS www..com Code No: N0321/R07 Set No. 1 1. a) What is a Superkey? With an example, describe the difference between a candidate key and the primary key for a given relation? b) With an example, briefly describe

More information

Babu Banarasi Das National Institute of Technology and Management

Babu Banarasi Das National Institute of Technology and Management Babu Banarasi Das National Institute of Technology and Management Department of Computer Applications Question Bank (Short-to-Medium-Answer Type Questions) Masters of Computer Applications (MCA) NEW Syllabus

More information

Techno India Batanagar Computer Science and Engineering. Model Questions. Subject Name: Database Management System Subject Code: CS 601

Techno India Batanagar Computer Science and Engineering. Model Questions. Subject Name: Database Management System Subject Code: CS 601 Techno India Batanagar Computer Science and Engineering Model Questions Subject Name: Database Management System Subject Code: CS 601 Multiple Choice Type Questions 1. Data structure or the data stored

More information

SQL Interview Questions

SQL Interview Questions SQL Interview Questions SQL stands for Structured Query Language. It is used as a programming language for querying Relational Database Management Systems. In this tutorial, we shall go through the basic

More information

CMSC 461 Final Exam Study Guide

CMSC 461 Final Exam Study Guide CMSC 461 Final Exam Study Guide Study Guide Key Symbol Significance * High likelihood it will be on the final + Expected to have deep knowledge of can convey knowledge by working through an example problem

More information

Chapter 13 : Concurrency Control

Chapter 13 : Concurrency Control Chapter 13 : Concurrency Control Chapter 13: Concurrency Control Lock-Based Protocols Timestamp-Based Protocols Validation-Based Protocols Multiple Granularity Multiversion Schemes Insert and Delete Operations

More information

Rajiv GandhiCollegeof Engineering& Technology, Kirumampakkam.Page 1 of 10

Rajiv GandhiCollegeof Engineering& Technology, Kirumampakkam.Page 1 of 10 Rajiv GandhiCollegeof Engineering& Technology, Kirumampakkam.Page 1 of 10 RAJIV GANDHI COLLEGE OF ENGINEERING & TECHNOLOGY, KIRUMAMPAKKAM-607 402 DEPARTMENT OF COMPUTER SCIENCE & ENGINEERING QUESTION BANK

More information

! A lock is a mechanism to control concurrent access to a data item! Data items can be locked in two modes :

! A lock is a mechanism to control concurrent access to a data item! Data items can be locked in two modes : Lock-Based Protocols Concurrency Control! A lock is a mechanism to control concurrent access to a data item! Data items can be locked in two modes : 1 exclusive (X) mode Data item can be both read as well

More information

Chapter 12 : Concurrency Control

Chapter 12 : Concurrency Control Chapter 12 : Concurrency Control Chapter 12: Concurrency Control Lock-Based Protocols Timestamp-Based Protocols Validation-Based Protocols Multiple Granularity Multiversion Schemes Insert and Delete Operations

More information

Advanced Databases. Lecture 9- Concurrency Control (continued) Masood Niazi Torshiz Islamic Azad University- Mashhad Branch

Advanced Databases. Lecture 9- Concurrency Control (continued) Masood Niazi Torshiz Islamic Azad University- Mashhad Branch Advanced Databases Lecture 9- Concurrency Control (continued) Masood Niazi Torshiz Islamic Azad University- Mashhad Branch www.mniazi.ir Multiple Granularity Allow data items to be of various sizes and

More information

AC61/AT61 DATABASE MANAGEMENT SYSTEMS JUNE 2013

AC61/AT61 DATABASE MANAGEMENT SYSTEMS JUNE 2013 Q2 (a) With the help of examples, explain the following terms briefly: entity set, one-to-many relationship, participation constraint, weak entity set. Entity set: A collection of similar entities such

More information

ROEVER ENGINEERING COLLEGE

ROEVER ENGINEERING COLLEGE ROEVER ENGINEERING COLLEGE ELAMBALUR, PERAMBALUR- 621 212 DEPARTMENT OF INFORMATION TECHNOLOGY DATABASE MANAGEMENT SYSTEMS UNIT-1 Questions And Answers----Two Marks 1. Define database management systems?

More information

Delhi Noida Bhopal Hyderabad Jaipur Lucknow Indore Pune Bhubaneswar Kolkata Patna Web: Ph:

Delhi Noida Bhopal Hyderabad Jaipur Lucknow Indore Pune Bhubaneswar Kolkata Patna Web:     Ph: Serial : 0. PT_CS_DBMS_02078 Delhi Noida Bhopal Hyderabad Jaipur Lucknow Indore Pune Bhubaneswar Kolkata Patna Web: E-mail: info@madeeasy.in Ph: 0-5262 CLASS TEST 208-9 COMPUTER SCIENCE & IT Subject :

More information

SYED AMMAL ENGINEERING COLLEGE

SYED AMMAL ENGINEERING COLLEGE UNIT-I INTRODUCTION TO DBMS CS6302- Database Management Systems Two Marks 1. What is database? A database is logically coherent collection of data with some inherent meaning, representing some aspect of

More information

Chapter 15 : Concurrency Control

Chapter 15 : Concurrency Control Chapter 15 : Concurrency Control What is concurrency? Multiple 'pieces of code' accessing the same data at the same time Key issue in multi-processor systems (i.e. most computers today) Key issue for parallel

More information

2 nd Semester 2009/2010

2 nd Semester 2009/2010 Chapter 16: Concurrency Control Departamento de Engenharia Informática Instituto Superior Técnico 2 nd Semester 2009/2010 Slides baseados nos slides oficiais do livro Database System Concepts c Silberschatz,

More information

CHAPTER 3 RECOVERY & CONCURRENCY ADVANCED DATABASE SYSTEMS. Assist. Prof. Dr. Volkan TUNALI

CHAPTER 3 RECOVERY & CONCURRENCY ADVANCED DATABASE SYSTEMS. Assist. Prof. Dr. Volkan TUNALI CHAPTER 3 RECOVERY & CONCURRENCY ADVANCED DATABASE SYSTEMS Assist. Prof. Dr. Volkan TUNALI PART 1 2 RECOVERY Topics 3 Introduction Transactions Transaction Log System Recovery Media Recovery Introduction

More information

DATABASE MANAGEMENT SYSTEM SHORT QUESTIONS. QUESTION 1: What is database?

DATABASE MANAGEMENT SYSTEM SHORT QUESTIONS. QUESTION 1: What is database? DATABASE MANAGEMENT SYSTEM SHORT QUESTIONS Complete book short Answer Question.. QUESTION 1: What is database? A database is a logically coherent collection of data with some inherent meaning, representing

More information

transaction - (another def) - the execution of a program that accesses or changes the contents of the database

transaction - (another def) - the execution of a program that accesses or changes the contents of the database Chapter 19-21 - Transaction Processing Concepts transaction - logical unit of database processing - becomes interesting only with multiprogramming - multiuser database - more than one transaction executing

More information

Foundation of Database Transaction Processing. Copyright 2012 Pearson Education, Inc.

Foundation of Database Transaction Processing. Copyright 2012 Pearson Education, Inc. Foundation of Database Transaction Processing Copyright 2012 Pearson Education, Inc. Chapter Outline - 17.1 Introduction to Transaction Processing - 17.2 Transaction and System Concepts - 17.3 Desirable

More information

CS411 Database Systems. 05: Relational Schema Design Ch , except and

CS411 Database Systems. 05: Relational Schema Design Ch , except and CS411 Database Systems 05: Relational Schema Design Ch. 3.1-3.5, except 3.4.2-3.4.3 and 3.5.3. 1 How does this fit in? ER Diagrams: Data Definition Translation to Relational Schema: Data Definition Relational

More information

Lecture 22 Concurrency Control Part 2

Lecture 22 Concurrency Control Part 2 CMSC 461, Database Management Systems Spring 2018 Lecture 22 Concurrency Control Part 2 These slides are based on Database System Concepts 6 th edition book (whereas some quotes and figures are used from

More information

Sankalchand Patel College of Engineering, Visnagar B.E. Semester III (CE/IT) Database Management System Question Bank / Assignment

Sankalchand Patel College of Engineering, Visnagar B.E. Semester III (CE/IT) Database Management System Question Bank / Assignment Sankalchand Patel College of Engineering, Visnagar B.E. Semester III (CE/IT) Database Management System Question Bank / Assignment Introductory concepts of DBMS 1. Explain detailed 3-level architecture

More information

Administration Naive DBMS CMPT 454 Topics. John Edgar 2

Administration Naive DBMS CMPT 454 Topics. John Edgar 2 Administration Naive DBMS CMPT 454 Topics John Edgar 2 http://www.cs.sfu.ca/coursecentral/454/johnwill/ John Edgar 4 Assignments 25% Midterm exam in class 20% Final exam 55% John Edgar 5 A database stores

More information

In This Lecture. Exam revision. Main topics. Exam format. Particular topics. How to revise. Exam format Main topics How to revise

In This Lecture. Exam revision. Main topics. Exam format. Particular topics. How to revise. Exam format Main topics How to revise In This Lecture Exam format Main topics How to revise Database Systems Lecture 18 Natasha Alechina Exam format Answer three questions out of five Each question is worth 25 points I will only mark three

More information

Transaction Management

Transaction Management Transaction Management 1) Explain properties of a transaction? (JUN/JULY 2015) Transactions should posses the following (ACID) properties: Transactions should possess several properties. These are often

More information

Chapter 20 Introduction to Transaction Processing Concepts and Theory

Chapter 20 Introduction to Transaction Processing Concepts and Theory Chapter 20 Introduction to Transaction Processing Concepts and Theory - Logical units of DB processing - Large database and hundreds of transactions - Ex. Stock market, super market, banking, etc - High

More information

Unit 2. Unit 3. Unit 4

Unit 2. Unit 3. Unit 4 Course Objectives At the end of the course the student will be able to: 1. Differentiate database systems from traditional file systems by enumerating the features provided by database systems.. 2. Design

More information

A7-R3: INTRODUCTION TO DATABASE MANAGEMENT SYSTEMS

A7-R3: INTRODUCTION TO DATABASE MANAGEMENT SYSTEMS A7-R3: INTRODUCTION TO DATABASE MANAGEMENT SYSTEMS NOTE: 1. There are TWO PARTS in this Module/Paper. PART ONE contains FOUR questions and PART TWO contains FIVE questions. 2. PART ONE is to be answered

More information

DHANALAKSHMI COLLEGE OF ENGINEERING, CHENNAI

DHANALAKSHMI COLLEGE OF ENGINEERING, CHENNAI DHANALAKSHMI COLLEGE OF ENGINEERING, CHENNAI Department of Computer Science and Engineering CS6302- DATABASE MANAGEMENT SYSTEMS Anna University 2 & 16 Mark Questions & Answers Year / Semester: II / III

More information

References. Transaction Management. Database Administration and Tuning 2012/2013. Chpt 14 Silberchatz Chpt 16 Raghu

References. Transaction Management. Database Administration and Tuning 2012/2013. Chpt 14 Silberchatz Chpt 16 Raghu Database Administration and Tuning 2012/2013 Transaction Management Helena Galhardas DEI@Técnico DMIR@INESC-ID Chpt 14 Silberchatz Chpt 16 Raghu References 1 Overall DBMS Structure Transactions Transaction

More information

T ransaction Management 4/23/2018 1

T ransaction Management 4/23/2018 1 T ransaction Management 4/23/2018 1 Air-line Reservation 10 available seats vs 15 travel agents. How do you design a robust and fair reservation system? Do not enough resources Fair policy to every body

More information

A can be implemented as a separate process to which transactions send lock and unlock requests The lock manager replies to a lock request by sending a lock grant messages (or a message asking the transaction

More information

CS6302 DBMS 2MARK & 16 MARK UNIT II SQL & QUERY ORTIMIZATION 1. Define Aggregate Functions in SQL? Aggregate function are functions that take a collection of values as input and return a single value.

More information

Database Management System Prof. D. Janakiram Department of Computer Science & Engineering Indian Institute of Technology, Madras Lecture No.

Database Management System Prof. D. Janakiram Department of Computer Science & Engineering Indian Institute of Technology, Madras Lecture No. Database Management System Prof. D. Janakiram Department of Computer Science & Engineering Indian Institute of Technology, Madras Lecture No. # 18 Transaction Processing and Database Manager In the previous

More information

CS322: Database Systems Transactions

CS322: Database Systems Transactions CS322: Database Systems Transactions Dr. Manas Khatua Assistant Professor Dept. of CSE IIT Jodhpur E-mail: manaskhatua@iitj.ac.in Outline Transaction Concept Transaction State Concurrent Executions Serializability

More information

Final Review. May 9, 2017

Final Review. May 9, 2017 Final Review May 9, 2017 1 SQL 2 A Basic SQL Query (optional) keyword indicating that the answer should not contain duplicates SELECT [DISTINCT] target-list A list of attributes of relations in relation-list

More information

Final Review. May 9, 2018 May 11, 2018

Final Review. May 9, 2018 May 11, 2018 Final Review May 9, 2018 May 11, 2018 1 SQL 2 A Basic SQL Query (optional) keyword indicating that the answer should not contain duplicates SELECT [DISTINCT] target-list A list of attributes of relations

More information

This lecture. Databases -Normalization I. Repeating Data. Redundancy. This lecture introduces normal forms, decomposition and normalization.

This lecture. Databases -Normalization I. Repeating Data. Redundancy. This lecture introduces normal forms, decomposition and normalization. This lecture Databases -Normalization I This lecture introduces normal forms, decomposition and normalization (GF Royle 2006-8, N Spadaccini 2008) Databases - Normalization I 1 / 23 (GF Royle 2006-8, N

More information

UNIT 4 TRANSACTIONS. Objective

UNIT 4 TRANSACTIONS. Objective UNIT 4 TRANSACTIONS Objective To study about the transaction concepts. To know the recovery management. To have a clear understanding of concurrent executions. To know how these are facilitated in SQL.

More information

Chapter 9: Transactions

Chapter 9: Transactions Chapter 9: Transactions modified from: Database System Concepts, 6 th Ed. See www.db-book.com for conditions on re-use Chapter 9: Transactions Transaction Concept Transaction State Concurrent Executions

More information

Data about data is database Select correct option: True False Partially True None of the Above

Data about data is database Select correct option: True False Partially True None of the Above Within a table, each primary key value. is a minimal super key is always the first field in each table must be numeric must be unique Foreign Key is A field in a table that matches a key field in another

More information

Unit 10.5 Transaction Processing: Concurrency Zvi M. Kedem 1

Unit 10.5 Transaction Processing: Concurrency Zvi M. Kedem 1 Unit 10.5 Transaction Processing: Concurrency 2016 Zvi M. Kedem 1 Concurrency in Context User Level (View Level) Community Level (Base Level) Physical Level DBMS OS Level Centralized Or Distributed Derived

More information

A subquery is a nested query inserted inside a large query Generally occurs with select, from, where Also known as inner query or inner select,

A subquery is a nested query inserted inside a large query Generally occurs with select, from, where Also known as inner query or inner select, Sub queries A subquery is a nested query inserted inside a large query Generally occurs with select, from, where Also known as inner query or inner select, Result of the inner query is passed to the main

More information

DATABASE DESIGN I - 1DL300

DATABASE DESIGN I - 1DL300 DATABASE DESIGN I - 1DL300 Spring 2011 An introductory course on database systems http://www.it.uu.se/edu/course/homepage/dbastekn/vt11/ Manivasakan Sabesan Uppsala Database Laboratory Department of Information

More information

Chapter 15: Transactions

Chapter 15: Transactions Chapter 15: Transactions! Transaction Concept! Transaction State! Implementation of Atomicity and Durability! Concurrent Executions! Serializability! Recoverability! Implementation of Isolation! Transaction

More information

CHAPTER: TRANSACTIONS

CHAPTER: TRANSACTIONS CHAPTER: TRANSACTIONS CHAPTER 14: TRANSACTIONS Transaction Concept Transaction State Concurrent Executions Serializability Recoverability Implementation of Isolation Transaction Definition in SQL Testing

More information

CS2255 DATABASE MANAGEMENT SYSTEMS QUESTION BANK UNIT I

CS2255 DATABASE MANAGEMENT SYSTEMS QUESTION BANK UNIT I CS2255 DATABASE MANAGEMENT SYSTEMS CLASS: II YEAR CSE SEM:04 STAFF INCHARGE: Mr S.GANESH,AP/CSE QUESTION BANK UNIT I 2 MARKS List the purpose of Database System (or) List the drawback of normal File Processing

More information

Transaction Processing: Basics - Transactions

Transaction Processing: Basics - Transactions Transaction Processing: Basics - Transactions Transaction is execution of program that accesses DB Basic operations: 1. read item(x): Read DB item X into program variable 2. write item(x): Write program

More information

Q.1 Short Questions Marks 1. New fields can be added to the created table by using command. a) ALTER b) SELECT c) CREATE. D. UPDATE.

Q.1 Short Questions Marks 1. New fields can be added to the created table by using command. a) ALTER b) SELECT c) CREATE. D. UPDATE. ID No. Knowledge Institute of Technology & Engineering - 135 BE III SEMESTER MID EXAMINATION ( SEPT-27) PAPER SOLUTION Subject Code: 2130703 Date: 14/09/27 Subject Name: Database Management Systems Branches:

More information

Normalization. Murali Mani. What and Why Normalization? To remove potential redundancy in design

Normalization. Murali Mani. What and Why Normalization? To remove potential redundancy in design 1 Normalization What and Why Normalization? To remove potential redundancy in design Redundancy causes several anomalies: insert, delete and update Normalization uses concept of dependencies Functional

More information

Transaction Management

Transaction Management Instructional Objectives Upon completion of this Unit, students will be introduced to the following About Transaction Processing Transaction and System Concepts Desirable Properties of Transactions Schedules

More information

Database Design Theory and Normalization. CS 377: Database Systems

Database Design Theory and Normalization. CS 377: Database Systems Database Design Theory and Normalization CS 377: Database Systems Recap: What Has Been Covered Lectures 1-2: Database Overview & Concepts Lecture 4: Representational Model (Relational Model) & Mapping

More information

Database Management System 15

Database Management System 15 Database Management System 15 Trivial and Non-Trivial Canonical /Minimal School of Computer Engineering, KIIT University 15.1 First characterize fully the data requirements of the prospective database

More information

E.G.S. PILLAY ENGINEERING COLLEGE (An Autonomous Institution, Affiliated to Anna University, Chennai) Nagore Post, Nagapattinam , Tamilnadu.

E.G.S. PILLAY ENGINEERING COLLEGE (An Autonomous Institution, Affiliated to Anna University, Chennai) Nagore Post, Nagapattinam , Tamilnadu. 7CA0 DATABASE MANAGEMENT SYSTEMS Academic Year : 08-09 Programme : MCA Question Bank Year / Semester : I / I Course Coordinator: Ms.S.Visalatchy Course Objectives. To learn the fundamentals of data models

More information

Weak Levels of Consistency

Weak Levels of Consistency Weak Levels of Consistency - Some applications are willing to live with weak levels of consistency, allowing schedules that are not serialisable E.g. a read-only transaction that wants to get an approximate

More information

mywbut.com Concurrency Control

mywbut.com Concurrency Control C H A P T E R 1 6 Concurrency Control This chapter describes how to control concurrent execution in a database, in order to ensure the isolation properties of transactions. A variety of protocols are described

More information

Roadmap of This Lecture

Roadmap of This Lecture Transactions 1 Roadmap of This Lecture Transaction Concept Transaction State Concurrent Executions Serializability Recoverability Implementation of Isolation Testing for Serializability Transaction Definition

More information

Chapter 15: Transactions

Chapter 15: Transactions Chapter 15: Transactions Chapter 15: Transactions Transaction Concept Transaction State Concurrent Executions Serializability Recoverability Implementation of Isolation Transaction Definition in SQL Testing

More information

CS/B.Tech/CSE/New/SEM-6/CS-601/2013 DATABASE MANAGEMENENT SYSTEM. Time Allotted : 3 Hours Full Marks : 70

CS/B.Tech/CSE/New/SEM-6/CS-601/2013 DATABASE MANAGEMENENT SYSTEM. Time Allotted : 3 Hours Full Marks : 70 CS/B.Tech/CSE/New/SEM-6/CS-601/2013 2013 DATABASE MANAGEMENENT SYSTEM Time Allotted : 3 Hours Full Marks : 70 The figures in the margin indicate full marks. Candidates are required to give their answers

More information

Advances in Data Management Transaction Management A.Poulovassilis

Advances in Data Management Transaction Management A.Poulovassilis 1 Advances in Data Management Transaction Management A.Poulovassilis 1 The Transaction Manager Two important measures of DBMS performance are throughput the number of tasks that can be performed within

More information

Transactions and Concurrency Control. Dr. Philip Cannata

Transactions and Concurrency Control. Dr. Philip Cannata Transactions and Concurrency Control Dr. Philip Cannata 1 To open two SQLDevelopers: On the Mac do the following: click on the SQLDeveloper icon to start one instance from the command line run the following

More information

Chapter 13: Transactions

Chapter 13: Transactions Chapter 13: Transactions Transaction Concept Transaction State Implementation of Atomicity and Durability Concurrent Executions Serializability Recoverability Implementation of Isolation Transaction Definition

More information

Functional Dependencies and Finding a Minimal Cover

Functional Dependencies and Finding a Minimal Cover Functional Dependencies and Finding a Minimal Cover Robert Soulé 1 Normalization An anomaly occurs in a database when you can update, insert, or delete data, and get undesired side-effects. These side

More information

TRANSACTION PROPERTIES

TRANSACTION PROPERTIES Transaction Is any action that reads from and/or writes to a database. A transaction may consist of a simple SELECT statement to generate a list of table contents; it may consist of series of INSERT statements

More information

A lock is a mechanism to control concurrent access to a data item Data items can be locked in two modes:

A lock is a mechanism to control concurrent access to a data item Data items can be locked in two modes: Concurrency Control Concurrency Control Lock-Based and Tree-Based Protocols Timestamp-Based Protocols Validation-Based Protocols Multiple Granularity Multiversion Schemes Insert and Delete Operations Concurrency

More information

D.K.M COLLEGE FOR WOMEN(AUTONOMOUS),VELLORE DATABASE MANAGEMENT SYSTEM QUESTION BANK

D.K.M COLLEGE FOR WOMEN(AUTONOMOUS),VELLORE DATABASE MANAGEMENT SYSTEM QUESTION BANK D.K.M COLLEGE FOR WOMEN(AUTONOMOUS),VELLORE DATABASE MANAGEMENT SYSTEM QUESTION BANK UNIT I SECTION-A 2 MARKS 1. What is meant by DBMs? 2. Who is a DBA? 3. What is a data model?list its types. 4. Define

More information

Chapter 5. Concurrency Control Techniques. Adapted from the slides of Fundamentals of Database Systems (Elmasri et al., 2006)

Chapter 5. Concurrency Control Techniques. Adapted from the slides of Fundamentals of Database Systems (Elmasri et al., 2006) Chapter 5 Concurrency Control Techniques Adapted from the slides of Fundamentals of Database Systems (Elmasri et al., 2006) Chapter Outline Purpose of Concurrency Control Two-Phase Locking Techniques Concurrency

More information

UNIT IV TRANSACTION MANAGEMENT

UNIT IV TRANSACTION MANAGEMENT UNIT IV TRANSACTION MANAGEMENT The term transaction refers to a collection of operations that form a single logical unit of work. For instance, transfer of money from one account to another is a transaction

More information

Databases -Normalization I. (GF Royle, N Spadaccini ) Databases - Normalization I 1 / 24

Databases -Normalization I. (GF Royle, N Spadaccini ) Databases - Normalization I 1 / 24 Databases -Normalization I (GF Royle, N Spadaccini 2006-2010) Databases - Normalization I 1 / 24 This lecture This lecture introduces normal forms, decomposition and normalization. We will explore problems

More information

CS403- Database Management Systems Solved MCQS From Midterm Papers. CS403- Database Management Systems MIDTERM EXAMINATION - Spring 2010

CS403- Database Management Systems Solved MCQS From Midterm Papers. CS403- Database Management Systems MIDTERM EXAMINATION - Spring 2010 CS403- Database Management Systems Solved MCQS From Midterm Papers April 29,2012 MC100401285 Moaaz.pk@gmail.com Mc100401285@gmail.com PSMD01 CS403- Database Management Systems MIDTERM EXAMINATION - Spring

More information

Overview of Transaction Management

Overview of Transaction Management Overview of Transaction Management Chapter 16 Comp 521 Files and Databases Fall 2010 1 Database Transactions A transaction is the DBMS s abstract view of a user program: a sequence of database commands;

More information

The Relational Algebra

The Relational Algebra The Relational Algebra Relational Algebra Relational algebra is the basic set of operations for the relational model These operations enable a user to specify basic retrieval requests (or queries) 27-Jan-14

More information

Transactions. Prepared By: Neeraj Mangla

Transactions. Prepared By: Neeraj Mangla Transactions Prepared By: Neeraj Mangla Chapter 15: Transactions Transaction Concept Transaction State Concurrent Executions Serializability Recoverability Implementation of Isolation Transaction Definition

More information

Copyright 2007 Ramez Elmasri and Shamkant B. Navathe. Slide 17-1

Copyright 2007 Ramez Elmasri and Shamkant B. Navathe. Slide 17-1 Slide 17-1 Chapter 17 Introduction to Transaction Processing Concepts and Theory Chapter Outline 1 Introduction to Transaction Processing 2 Transaction and System Concepts 3 Desirable Properties of Transactions

More information

Transactions. Silberschatz, Korth and Sudarshan

Transactions. Silberschatz, Korth and Sudarshan Transactions Transaction Concept ACID Properties Transaction State Concurrent Executions Serializability Recoverability Implementation of Isolation Transaction Definition in SQL Testing for Serializability.

More information

Chapter 14: Transactions

Chapter 14: Transactions Chapter 14: Transactions Transaction Concept Transaction Concept A transaction is a unit of program execution that accesses and possibly updates various data items. E.g. transaction to transfer $50 from

More information

Introduction to Database Systems. Announcements CSE 444. Review: Closure, Key, Superkey. Decomposition: Schema Design using FD

Introduction to Database Systems. Announcements CSE 444. Review: Closure, Key, Superkey. Decomposition: Schema Design using FD Introduction to Database Systems CSE 444 Lecture #9 Jan 29 2001 Announcements Mid Term on Monday (in class) Material in lectures Textbook Chapter 1.1, Chapter 2 (except 2.1 and ODL), Chapter 3 (except

More information

Advanced Databases (SE487) Prince Sultan University College of Computer and Information Sciences. Dr. Anis Koubaa. Spring 2014

Advanced Databases (SE487) Prince Sultan University College of Computer and Information Sciences. Dr. Anis Koubaa. Spring 2014 Advanced Databases (SE487) Prince Sultan University College of Computer and Information Sciences Transactions Dr. Anis Koubaa Spring 2014 Outlines Transaction Concept Transaction State Implementation of

More information

Security Mechanisms I. Key Slide. Key Slide. Security Mechanisms III. Security Mechanisms II

Security Mechanisms I. Key Slide. Key Slide. Security Mechanisms III. Security Mechanisms II Database Facilities One of the main benefits from centralising the implementation data model of a DBMS is that a number of critical facilities can be programmed once against this model and thus be available

More information

Chapter 14: Transactions

Chapter 14: Transactions Chapter 14: Transactions Database System Concepts, 6 th Ed. See www.db-book.com for conditions on re-use Chapter 14: Transactions Transaction Concept Transaction State Concurrent Executions Serializability

More information

ADVANCED DATABASES ; Spring 2015 Prof. Sang-goo Lee (11:00pm: Mon & Wed: Room ) Advanced DB Copyright by S.-g.

ADVANCED DATABASES ; Spring 2015 Prof. Sang-goo Lee (11:00pm: Mon & Wed: Room ) Advanced DB Copyright by S.-g. 4541.564; Spring 2015 Prof. Sang-goo Lee (11:00pm: Mon & Wed: Room 301-203) ADVANCED DATABASES Copyright by S.-g. Lee Review - 1 General Info. Text Book Database System Concepts, 6 th Ed., Silberschatz,

More information

II B.Sc(IT) [ BATCH] IV SEMESTER CORE: RELATIONAL DATABASE MANAGEMENT SYSTEM - 412A Multiple Choice Questions.

II B.Sc(IT) [ BATCH] IV SEMESTER CORE: RELATIONAL DATABASE MANAGEMENT SYSTEM - 412A Multiple Choice Questions. Dr.G.R.Damodaran College of Science (Autonomous, affiliated to the Bharathiar University, recognized by the UGC)Re-accredited at the 'A' Grade Level by the NAAC and ISO 9001:2008 Certified CRISL rated

More information

BİL 354 Veritabanı Sistemleri. Transaction (Hareket)

BİL 354 Veritabanı Sistemleri. Transaction (Hareket) BİL 354 Veritabanı Sistemleri Transaction (Hareket) Example BUSEY SAVINGS Winslett $1000 Transfer $500 BUSEY CHECKING Winslett $0 A single operation from the customer point of view It comprises several

More information

Relational Design: Characteristics of Well-designed DB

Relational Design: Characteristics of Well-designed DB 1. Minimal duplication Relational Design: Characteristics of Well-designed DB Consider table newfaculty (Result of F aculty T each Course) Id Lname Off Bldg Phone Salary Numb Dept Lvl MaxSz 20000 Cotts

More information

Transaction Concept. Two main issues to deal with:

Transaction Concept. Two main issues to deal with: Transactions Transactions Transactions Transaction States Concurrent Executions Serializability Recoverability Implementation of Isolation Transaction Definition in SQL Testing for Serializability. Transaction

More information

Introduction to Transaction Processing Concepts and Theory

Introduction to Transaction Processing Concepts and Theory Chapter 4 Introduction to Transaction Processing Concepts and Theory Adapted from the slides of Fundamentals of Database Systems (Elmasri et al., 2006) 1 Chapter Outline Introduction to Transaction Processing

More information

CS Reading Packet: "Transaction management, part 2"

CS Reading Packet: Transaction management, part 2 CS 325 - Reading Packet: "Transaction management, part 2" p. 1 Sources: CS 325 - Reading Packet: "Transaction management, part 2" * Ricardo, "Databases Illuminated", Chapter 10, Jones and Bartlett. * Kroenke,

More information

Database Principles: Fundamentals of Design, Implementation, and Management Tenth Edition. Chapter 13 Managing Transactions and Concurrency

Database Principles: Fundamentals of Design, Implementation, and Management Tenth Edition. Chapter 13 Managing Transactions and Concurrency Database Principles: Fundamentals of Design, Implementation, and Management Tenth Edition Chapter 13 Managing Transactions and Concurrency Objectives In this chapter, you will learn: What a database transaction

More information

Lecture 20 Transactions

Lecture 20 Transactions CMSC 461, Database Management Systems Spring 2018 Lecture 20 Transactions These slides are based on Database System Concepts 6 th edition book (whereas some quotes and figures are used from the book) and

More information

Transactions These slides are a modified version of the slides of the book Database System Concepts (Chapter 15), 5th Ed

Transactions These slides are a modified version of the slides of the book Database System Concepts (Chapter 15), 5th Ed Transactions These slides are a modified version of the slides of the book Database System Concepts (Chapter 15), 5th Ed., McGraw-Hill, by Silberschatz, Korth and Sudarshan. Original slides are available

More information

Chapter 7 (Cont.) Transaction Management and Concurrency Control

Chapter 7 (Cont.) Transaction Management and Concurrency Control Chapter 7 (Cont.) Transaction Management and Concurrency Control In this chapter, you will learn: What a database transaction is and what its properties are What concurrency control is and what role it

More information

Database Systems. Basics of the Relational Data Model

Database Systems. Basics of the Relational Data Model Database Systems Relational Design Theory Jens Otten University of Oslo Jens Otten (UiO) Database Systems Relational Design Theory INF3100 Spring 18 1 / 30 Basics of the Relational Data Model title year

More information

Advanced Databases. Transactions. Nikolaus Augsten. FB Computerwissenschaften Universität Salzburg

Advanced Databases. Transactions. Nikolaus Augsten. FB Computerwissenschaften Universität Salzburg Advanced Databases Transactions Nikolaus Augsten nikolaus.augsten@sbg.ac.at FB Computerwissenschaften Universität Salzburg Version October 18, 2017 Wintersemester 2017/18 Adapted from slides for textbook

More information

Database Management Systems

Database Management Systems S.Y. B.Sc. (IT) : Sem. III Database Management Systems Time : 2½ Hrs.] Prelim Question Paper Solution [Marks : 75 Q.1 Attempt the following (any THREE) [15] Q.1 (a) Explain database system and give its

More information

Sample Exam for CSE 480 (2017) KEY

Sample Exam for CSE 480 (2017) KEY Sample Exam for CSE 480 (2017) KEY Answer the questions in the spaces provided on the page. If you run out of room for an answer, continue on the back of that page. Instructions: DO NOT START THE EXAM

More information

ICOM 5016 Database Systems. Chapter 15: Transactions. Transaction Concept. Chapter 15: Transactions. Transactions

ICOM 5016 Database Systems. Chapter 15: Transactions. Transaction Concept. Chapter 15: Transactions. Transactions ICOM 5016 Database Systems Transactions Chapter 15: Transactions Amir H. Chinaei Department of Electrical and Computer Engineering University of Puerto Rico, Mayagüez Slides are adapted from: Database

More information