BHARATHIDASAN ENGINEERING COLLEGE NATTRAMPALLI Second Year CSE/IT III SEMESTER UPDATED FAQ s Subject: CS6302/DBMS

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1 BHARATHIDASAN ENGINEERING COLLEGE NATTRAMPALLI Second Year CSE/IT III SEMESTER UPDATED FAQ s Subject: CS6302/DBMS UNIT- I PART-A 1.Why 4NF in Normal Form is more desirable than BCNF? NOV/DEC NF is more desirable than BCNF because it reduces the repetition of information. If we consider a BCNF schema not in 4NF, we observe that decomposition into 4NF does not lose information provided that a lossless join decomposition is used, yet redundancy is reduced. 2.What is the purpose of DBMS? NOV/DEC 2014, NOV/DEC 2016 ANS: Data redundancy and inconsistency Difficulty in accessing data Data isolation Integrity problems Atomicity of updates Concurrent access by multiple users Security problems 3.Write the characteristics that distinguish the database approach with the file-based approach. APR/MAY 2015,NOV/DEC 2016 ANS: 1. Storage layer 2. Low level storage management 3. Transaction & concurrency control management 4. Data Manipulation Language 5. Data access facilities 6. Data dictionary 7. Network access 4.Define Functional Dependency. APR/MAY 2015 ANS: Functional dependency is a relationship that exists when one attribute uniquely determines another attribute. If R is a relation with attributes X and Y, a functional dependency between the attributes is represented as X->Y, which specifies Y is functionally dependent on X. 5.Define Data model and what are the types of data models? ANS: It is a set of concepts to describe the structure of a database, and certain constraints that the database should obey. Three types of data models are: 1.Entity relationship model 2.Relational model 3.hierarchical model 4.network model 5.object oriented model

2 6.Define primary key. NOV/DEC 2016 ANS: A primary key, also called a primary keyword, is a key in a relational database that is unique for each record. It is a unique identifier, such as a telephone number. 7.List any eight applications of DBMS. ANS: Banking, Airlines, Sales, Finance, Tele communication, Universities, Credit card transactions, Manufacturing 8.What are the levels of data abstraction? ANS: Physical level Logical level View level 9.Define De normalization. ANS: The process of storing the job of higher normal form relations as base relations which lower normal is known as De-normalization. 10.Describe the two types of participation constraint. ANS: 1.Total Participation: The participation of an entity set E in a relationship set R is said to be total if every entity in E participates in at least one relationship in R 2.Partial participation: if only some entities in E participate in relationships in R, the participation of entity set E in relationship R is said to be partial. 11.Who is DBA? What are the responsibilities of DBA? A database administrator is a person responsible for the design, implementation, maintenance and repair of an organization s database. The roles include the development and design of database strategies, monitoring and improving database performance and capacity and planning for future expansion requirements. 12.Define DBMS. A DBMS is a collection of interrelated data and set of programs to access those data. DBMS is a set of prewritten programs used to store, update and retrieve a database 13.Write any six terms related with DBMS. Data, information, database, table, record, fields 14.What is database schema? The overall design of the database is called database schema. 15.Define instance. The collection of information stored in the database at a particular moment is called an instance of the database. 16.What is meant by system catalog(data dictionary)? It is a repository of information describing the data in the database, that is the metadata(or data about the data ).

3 17.Define relational algebra. It is a procedural query language. It consists of a set of operations that take one or two operations as input and produce a new relation as their output. 18.What do you mean by Query language? It is a language in which a user requests information from the database. 19.What are the fundamental operations of relational algebra? Union, intersection, difference, Cartesian product, 20.What are the additional operations of relational algebra? Set intersection, natural join, division operation, assignment operation 21.What are the types of attributes in ER model? Simple, composite, single-valued, multi-valued, derived 22.Define super key. NOV/DEC 2016 It is a set of one or more attributes that allows us to identify uniquely an entity in the entity set. 23.Define primary key. NOV/DEC 2016 It is a candidate key that is chosen by the database designer as the principal means of identifying entities within an entity set. For example, roll_no is a primary key of student entity set. 24.What are the purposes of normalization? It minimizes redundancy in data It removes insert, delete and update anamoly during database activities It reduces the need to reorganize data when it is modified or enhanced. 25.What are the types of normalization? First normal form, second normal form, third normal form, boyce-codd normal form, fourth normal form, fifth normal form, domain key normal form 26.Define domain key normal form. It is a normal form used in database normalization which requires that the database contains no constraints other than domain constraints. 27.Define denormalization. It presents a trade-off between performance and modification anomalies/data redundancy. 28.What are the disadvantages of file processing system? MAY/JUNE Explain Entity-relationship model. MAY/JUNE In what way DB users can be differentiated? NOV/DEC List out any two keys. NOV/DEC What is a weak entity? Give example. NOV/DEC State the anomalies of 1NF. NOV/DEC 2015

4 34.Is it possible for several attributes to have the same domain? Illustrate your answer with suitable examples. NOV/DEC 2015 UNIT I PART-B 1.What is Data model? Explain various types of data model. NOV/DEC Draw an E-R Diagram for Banking system. NOV/DEC Explain the components of DBMS with a neat sketch./briefly Explain about database system architecture. APR/MAY 2015, NOV/DEC 2015, MAY/JUNE Write short notes on codd s Rule. 5.Write short notes on Functional dependency and Anomaly 6.Draw E-R diagram for the Restaurant Menu Ordering System which will facilitate the food items ordering and services within a restaurant. APR/MAY What are Normal forms. Explain the types of Normal form with an example. APR/MAY 2015, NOV/DEC 2014, NOV/DEC Explain relational algebra operations with an example./explain select, project and Cartesian product operations in relational algebra with an example.(6) NOV/DEC Explain File systems organization in detail. 10.What are the characteristics of database? 11.Explain ER model with an example. 12.Compare specialization and generalization. 13.Construct an ER diagram for a hospital with a set of patients and a set of medical doctors. 14.Briefly explain about views of data. MAY/JUNE Construct an ER diagram for a car insurance company./car rental company database. NOV/DEC 2015, NOV/DEC What are the advantages of having a centralized control of data? Illustrate your answer with suitable example. NOV/DEC Describe the six clauses in the syntax of an SQL query, and show what type of constructs can be specified in each of the six clauses.which of the six clauses are required and which are optional? NOV/DEC 2015

5 UNIT II PART-A 1.Differentiate between Dynamic SQL and Static SQL. APR/MAY 2015, NOV/DEC 2015, NOV/DEC 2014, NOV/DEC 2016 ANS: STATIC SQL(EMBEDDED) In static SQL how database will be accessed is predetermined in the embedded SQL statement. DYNAMIC SQL(INTERACTIVE) In dynamic SQL, how database will be accessed is determined at run time It is more efficient. It is less efficient. SQL statements are compiled at compile time. SQL statements are compiled at run time. Parsing, validation, optimization, and generation of application plan are done at compile time. Parsing, validation, optimization, and generation of application plan are done at run time. It is generally used for situations where data is distributed uniformly. It is generally used for situations where data is distributed nonuniformly. EXECUTE IMMEDIATE, EXECUTE and PREPARE statements are not used. EXECUTE IMMEDIATE, EXECUTE and PREPARE statements are used. It is less flexible. It is more flexible. 2.Define Relational Algebra. List out its operators. ANS: Relational algebra is a formal system for manipulating relations. Operands of this algebra are relations. special operations defined for relations. selection. projection. 3.State the need for Query Optimization. APR/MAY 2015,MAY/JUNE Define Triggers. ANS: The query optimizer attempts to determine the most efficient way to execute a given query by considering the possible query plans. ANS: Triggers are statements that are executed automatically by the system as the side effect of a modification to the database.

6 5.What is the use of aggregate functions in SQL? ANS: Aggregate functions are functions that takes a collection of values as input and return a single value. Aggregate functions supported by SQL are: Average: avg Minimum: min Maximum: max Total: sum Count: count 6.Define SQL and SQL data types. ANS: SQL (Structured Query Language) is a standard interactive and programming language for getting information from and updating a database. Data type CHARACTER(n) VARCHAR(n) or CHARACTER VARYING(n) BINARY(n) BOOLEAN Description Character string. Fixed-length n Character string. Variable length. Maximum length n Binary string. Fixed-length n Stores TRUE or FALSE values 7.Define Schemas in SQL. ANS: A schema is a collection of database objects (tables) associated with one particular database username. This username is called the schema owner, You may have one or multiple schemas in a database. 8.Define Data dictionary. ANS: A data dictionary is a collection of descriptions of the data objects or items in a data model for the benefit of programmers and others who need to refer to them. 9.Specify internal representation of a Query. ANS: Two representation of a query 1.Query Graph 2.Query Tree 10.What is Embedded SQL? ANS: Embedded SQL is a method of inserting inline SQL statements or queries into the code of a programming language, which is known as a host language. 11.What is called query processing? List out the steps in it. Query processing refers to the range of activities involved in extracting data from a database. The basic steps are 1. Parsing and translation 2. Optimization 3. Evaluation

7 12.What are the categories of SQL command? MAY/JUNE 2016 DDL(Data Definition Language) DML(Data manipulation Language) DCL(Data Control Language) TCL(Transaction Control Language) 13.What is the use of rename operation? Rename operation is used to rename both relations and attributes. It takes the form: Old-name as new-name 14.List the set operations of SQL. Union, Intersect, except operation 15.List the string operations supported by SQL. 1 Pattern matching operation 2 Concatenation 3 Extracting character strings 4 Converting between uppercase and lowercase letters 16.What are aggregate functions and list the aggregate functions supported by SQL? Aggregate functions are functions that take a collection of values as input and return a single value. Aggregate functions supported by SQL Average: avg Maximum: max Minimum: min Count: count Total: sum 17.What are different types of SQL operators? Arithmetic operators Comparison operators Logical operators Set operators 18.Define DB objects and its types. A DB object is any defined object in a database that is used to store or reference data. Some examples of DB objects include tables, views, clusters, sequences, indexes, and synonyms.

8 19.Define join and its types. Join is a query in which data is retrieved from two or more table. Different types of joins are: Inner join Outer join(left outer, right outer, full outer) Natural join 20.Define DCL. and what are its commands? NOV/DEC 2014 It is a computer language and a subset of SQL, used to control access to data in a database. Examples of DCL commands include: GRANT: used to allow specified users to perform specified tasks. REVOKE: used to cancel previously granted permissions. 21.How the cost of a query is evaluated? The cost of a query evaluation can be measured in terms of a number of different resources, including disk accesses, CPU time to execute a query and the cost of communication. 22.Define Query tree. A tree data structure that corresponds to a relational algebra expression. 23.Define Query graph. A graph data structure that corresponds to a relational calculus expression. 24.What are the cost components for query execution? Access cost to secondary storage Storage cost Computation cost Memory usage cost Communication cost 25.What are the commands are used in DDL?/What is data definition language?give example. NOV/DEC 2016 Create-create a new table Alter altering the existing table Drop-dropping the database Rename-renaming the existing table Truncate-deleting the table

9 26.What are the commands are used in DML? Select-select records from a table Insert-insert new records Update-modify existing record Delete-deleting existing records 27.What are the types of DCL commands? GRANT-to provide access or privileges on the DB objects to the users REVOKE-removes user success rights or privileges to the DB objects 28.What are the commands are used in TCL? COMMIT-to save the changes ROLLBACK-to rollback the changes SAVEPOINT-create points within groups of transactions in which to rollback 29.Give the difference between ODBC and JDBC. NOV/DEC Why does SQL allow duplicate tuples in a table or in a query result? NOV/DEC 2016 UNIT II PART-B 1.Explain different types of SQL DDL commands. NOV/DEC 2014,MAY/JUNE Give a detailed description about Query processing and Optimization. MAY/JUNE 2016, NOV/DEC Explain different types of SQL DML commands. NOV/DEC APR/MAY Explain different types of SQL DCL,TCL commands. 5.Explain about SQL fundamentals. MAY/JUNE Explain join operation in SQL. 7.Explain various aggregate functions available in SQL. 8.Compare i)outer join and full outer join ii)left outer join and right outer join APR/MAY Explain the cost estimation of Query optimization NOV/DEC What is the role of relational algebra in query processing? NOV/DEC Explain briefly about embedded SQL. NOV/DEC 2014,NOV/DEC Differentiate between static and dynamic SQL. 13.Explain the importance of query optimization. NOV/DEC Explain (i)nested loop join (ii)block nested loop join (iii)merge join

10 (iv)hash join NOV/DEC Discuss about the join order optimization and heuristic optimization algorithms. APR/MAY 2015 UNIT III PART -A 1.Define the properties of Transaction. APR/MAY 2015, NOV/DEC 2014,MAY/JUNE 2016 ANS: ACID Properties. A transaction is a very small unit of a program and it may contain several low level tasks. A transaction in a database system must maintain Atomicity, Consistency, Isolation, and Durability commonly known as ACID properties in order to ensure accuracy, completeness, and data integrity. 2.What is Serializability? How it is tested? NOV/DEC 2014 NOV/DEC 2016 ANS: A (possibly concurrent) schedule is serializable if it is equivalent to a serial schedule. Different forms of schedule equivalence give rise to the notions of: Conflict serializability View serializability 3.Define : DDL,DML,DCL and TCL. APR/MAY 2015 ANS: DDL Database system provides DDL to specify the database schema. DML Database system provides DML to express the database queries and updates DCL -- A data control language (DCL) is used to control access to data stored in a database (Authorization). Examples of DCL commands include: GRANT to allow specified users to perform specified tasks. TCL-- A Transaction Control Language (TCL) is used to control transactional processing in a database. 4.What are the Transaction states? ANS: Active This is the initial state. The transaction stay in this state while it is executing. Partially Committed This is the state after the final statement of the transaction is executed.

11 Failed After the discovery that normal execution can no longer proceed. Aborted The state after the transaction has been rolled back and the database has been restored to its state prior to the start of the transaction. Committed The state after successful completion of the transaction. We cannot abort or rollback a committed transaction. 5.What do you mean by Concurrency Control? NOV/DEC 2015 ANS: Concurrency control schemes are based on the serializability property. Different types of protocols/schemes to used to control concurrent execution of transactions are Lock based protocols Timestamp based protocol 6.Define Deadlock and how it can be detected. ANS: a deadlock is a situation in which two or more transactions are waiting for one another to give up locks. For example, Transaction A might hold a lock on some rows in the Accounts table and needs to update some rows in the Orders table to finish. 7.What is the Two-Phase Locking protocol (2PL)? NOV/DEC What do you mean by conflict serializable? ANS: Growing phase: a transaction may obtain locks but not release any lock. Shrinking phase: a transaction may release locks but may not obtain any new locks. ANS: Two schedules are said to be conflict equivalent if the order of any two conflicting operations is the same in both schedules. 9.What is S-Lock and X-Lock? ANS: Exclusive Lock(X-Lock):Data item can be both read as well as Written. X-Lock is requested using lock-x instruction. Shared Lock(S-Lock):Data item can only be read. S-Lock is requested using lock-s instruction. 10.Mention the deadlock prevention strategies./four conditions for deadlock. NOV/DEC 2016 ANS: i)require that each transaction locks all its data items before it begins execution. ii)impose partial ordering of all data items. iii)timeout-based schemes. iv)use time stamping. 11.Define timestamp based protocols. This protocol ensures serializability. It selects an ordering among transactions in advance using timestamps.

12 12.What are the pitfalls(problem) of lock based protocols? Deadlock Starvation 13.what are the two statements regarding transaction? Begin transaction End transaction 14.What is transaction? Collections of operations that form a single logical unit of work are called transactions. 15.Define deadlock. A deadlock occurs when two or more tasks permanently block each otherby each task having a lock on a resource which the other tasks are trying to lock. 16.Define the phases of two phase locking protocol. Growing phase: a transaction may obtain locks but not release any lock. Shrinking phase: a transaction may release locks but may not obtain any new locks. 17.What are the two methods for dealing deadlock problem? 1)deadlock detection 2)deadlock recovery 18.What are the two types of errors? Logical error System error 19.What are the storage types? Volatile storage Non volatile storage 20.What are the two types of rollback? Total rollback Partial rollback 21.Define starvation. In a system where the selection of victims is based primarily on cost factors, it may happen that the same transaction is always picked as a victim. As a result, this transaction never completes its designated task, thus there is starvation. 22.What are the two different deadlock prevention schemes using timestamp? Wait die Wound wait

13 23.What are the problems occurred in concurrent execution? 1.Lost update 2.Dirty read 3.Unrepeatable read 24.What are the timestamps associated with each data item? W-timestamp(Q) denotes the largest timestamp if any transaction that executed WRITE(Q) successfully R-timestamp(Q) denotes the largest timestamp if any transaction that executed READ(Q) successfully 25.Define disk buffer. The area of memory where blocks reside temporarily is called the disk buffer. 26.Define page. The database is partitioned into some number of fixed-length blocks, which are called as page. 27.Differentiate strict two-phase locking protocol and rigorous two phase locking protocol. MAY/JUNE 2016 UNIT III PART-B 1.What is Concurrency? Explain it in terms of locking mechanism and Two phase Commit protocol. NOV/DEC 2014, NOV/DEC 2015, APR/MAY 2015,MAY/JUNE 2016, NOV/DEC Write short notes on Transaction Concepts. NOV/DEC Outline Deadlock handling mechanisms. NOV/DEC 2014, NOV/DEC Explain different states of a transaction. 5.Describe briefly conflict serializability and view serializability. NOV/DEC Define deadlock. Explain the methods used to prevent deadlock. NOV/DEC Explain the methods used to detect and recover from deadlock. NOV/DEC What benefits does rigorous two-phase locking provide? How does it compare with other forms of two-phase locking? 9.Explain timestamp ordering protocol with an example. 10.Define lock and state different types of locks. NOV/DEC What benefits does strict two-phase locking provide? What disadvantages result? 12.Explain about locking protocols. MAY/JUNE Explain Three-phase commit protocols. APR/MAY 2015

14 UNIT IV PART-A 1.What are the advantages and disadvantages of indexed sequential file? Advantages: search the file more quickly, fast searches if we know the key value Disadvantages: very expensive inserts, a search uses index. 2.Compare sequential and random access devices with an example. SEQUENTIAL ACCESS DEVICE Must be accessed from the beginning Access to data is much slower Eg:tape storage RANDOM ACCESS DEVICE to read data from any location cheaper than disk Eg.disk storage 3.Give the measures of quality of a disk. Capacity Access time Seek time Data transfer rate Rotational latency time 4.What are called jukebox systems? It contains few drives and numerous disks that can be loaded into of the drives automatically. 5.Define access time. It is time from when a read or write request is issued to when data transfer begins. 6.Define seek time. The time for repositioning the arm is called the seek time. 7.Define rotational latency time. The time spent waiting for the sector to be accessed to appear under the head is called rotational latency time. 8.What is meant by data-transfer rate? disk. The data-transfer rate is the rate at which data can be retrieved from or stored to the 9.What is the use of RAID? A variety of disk-organization techniques, collectively called redundant arrays of independent disks are used to improve the performance and reliability. 10.What is called mirroring? The simplest approach to introducing redundancy is to duplicate every disk.this technique is called mirroring or shadowing. 11.What is called mean time to repair? It is the time it takes to replace a failed disk and to restore the data on it.

15 12.What is called bit-level striping? Data striping consists of splitting the bits of each byte across multiple disks. This is called bit-level striping. 13.What is called block-level striping? Block level striping stripes blocks across multiple disks. It treats the array of disks as a large disk, and gives blocks logical numbers. 14.Which level of RAID is best? Why? RAID level 1 is the RAID level of choice for many applications with moderate storage requirements and high I/O requirements. RAID 1 follows mirroring and provides best write performance. 15.What is an index? An index is a structure that helps to locate desired records of a relation quickly, without examining all records. 16.What are the two types of ordered indices? Primary index Secondary index 17.What are the types if indices? Ordered indices Hash indices 18.What are the techniques to be evaluated for both ordered indexing and hashing? Access types Access time Insertion time Deletion time Space overhead 19.What is a primary index? file. A primary index is an index whose search key also defines the sequential order of the 20.What is a B+ tree index? It takes the form of a balanced tree in which every path from the root to a leaf is of the same length. 21.What is B- tree? It eliminates the redundant storage of search-key values. It allows search key values to appear only once. 22.What is hashing? It allows us to find the address of a data itemdirectly by computing a hash function on the search key value of the desired record.

16 23.Differentiate static and dynamic hashing. NOV/DEC 2015, APR/MAY 2015,NOV/DEC 2014 Static hashing uses a hash function in which the set of bucket address is fixed. Dynamic hashing allows us to modify the hash function dynamically. 24.What is an hash index? A hash index organizes the search keys with their associated pointers, into a hash file structure. 25.What is linear probing? Linear probing is a type of open hashing. If a bucket is full, the system inserts records into the next bucket that has space. this is called linear probing. 26.What is meant by hash join? In the hash join algorithm, a hash function h is used to implement partition tuples of both relations. 27.What is meant by garbage collection? MAY/JUNE Define software and hardware RAID systems. MAY/JUNE List out the mechanisms to avoid collision during hashing. NOV/DEC 2015, NOV/DEC What are the disadvantages of B Tree over B+ tree? NOV/DEC Define data mining and data warehousing. NOV/DEC Write about four types(star, Snowflake, galaxy, fact constellation)of data warehouse schemas APR/MAY Give an example of a join that is not a simple equi-join for which partitioned parallelism can be used. NOV/DEC 2015 UNIT IV PART-B 1.What is RAID? List the different levels in RAID technology and explain its features. NOV/DEC 2014, APR/MAY 2015, NOV/DEC 2015, MAY/JUNE 2016, NOV/DEC Briefly explain about B+ tree index file with an example. 3.Explain the architectural components of a data warehouse and write about data marts. APR/MAY 2015, NOV/DEC Write short notes on Spatial databases. NOV/DEC 2014, NOV/DEC 2015,NOV/DEC Write short notes on mobile databases. NOV/DEC 2014 NOV/DEC Explain in detail about B+ tree index with example. NOV/DEC 2014,MAY/JUNE Explain in detail about B- tree index. NOV/DEC Write down short notes on ordered indices and B- tree index files. 9.Construct a B+ tree to insert the following key elements 5,3,4,9,7,15,14,21,22, Describe the features of multimedia databases. NOV/DEC 2015

17 11.Write a short note on web databases. NOV/DEC Explain in detail about multidimensional and parallel databases. 13.Explain the workflow of magnetic disk storage system. 14.describe in detail about how records are represented in a file and how to organize them in a file. 15.write the features data mining. APR/MAY Explain the architecture of a distributed database system.(7) NOV/DEC Illustrate indexing and hashing techniques with suitable examples. NOV/DEC What does database security refer to? UNIT V PART-A It refers to the protection from unauthorized access and malicious alteration. 2.List some security violations(or) name any forms of malicious access. Unauthorized reading of data Unauthorized modification of data Unauthorized destruction of data 3.List the types of authorization. Read authorization write authorization update authorization drop authorization 4.What is authorization graph? Passing of authorization from one user to another can be represented by an authorization graph. 5.What are audit trails? It is a log of all changes to the database along with information such as which user performed the change and when the change was performed. 6.Define distributed systems. Data spread over multiple machines(sites or nodes).network interconnects the machines. data shared by users on multiple machines. 7.define cryptography. It is technique of encoding and decoding messages, so that they are not understood by anybody except the sender and the intended recipient. 8.What is homogeneous distributed databases? Same software/schema on all sites, data may be partitioned among sites. The goal is to provide a view of a single database, hiding details of distribution.

18 9. What is heterogeneous distributed databases? Different software/schema on different sites. The goal is to integrate existing databases to provide useful functionality. 10.mention the various levels in security measures. Database system Operating system Network Physical Human 11.what is data mining(data or knowledge discovery)? NOV/DEC 2014 It is the process of analysing data from different perspectives and summarizing it into useful information. 12.Define statistical databases. It is used for statistical analysis purposes. It is an OLAP, instead of OLTP. 13.Define object oriented database. It is a database management system in which information is represented in the form of objects as used in object oriented programming. 14.what is a XML database? It is a data persistence software system that allows data to be stored in XML format. These data can then be queried, exported and serialized into the desired format. 15.Explain the basic failure types in a distributed environment. Failure of a site Failure of communication link Network partition 16.Define RSA algorithm. It is a public-key cryptosystems and is widely used for secure data transmission. A user of RSA creates and then publishes a public key based on two large prime numbers, along with an auxiliary value 17.Define confidentiality. The principle of confidentiality specifies that only the sender and the intended recipient(s) should be able to access the contents of a message. 18.Define discretionary control. This is a database control, in which the users of the database system have access rights, this is also called privileges. 19.Define privilege. And what are its types? NOV/DEC 2015 Types: It is a right to execute a particular type of statement or to access another user s object, a)system privileges b)object privileges

19 20.What are the types of cryptography? Symmetric key cryptography Asymmetric key cryptography 21.What are the types multiprocessor system architectures? Shared memory(tightly coupled) architecture Shared disk(loosely coupled) architecture 22.what are the types of distributed architectures? Shared memory systems Shared disk systems Shared nothing systems 23.define replication. If relation R is replicated, a copy of relation R is stored in two or more sites. 24.Define data fragmentation. If relation r is fragmented, r is divided into a number of fragments r1,r2,,rn. These fragments contain sufficient information to allow reconstruction of the original relation Types: a)horizontal fragmentation b)vertical fragmentation 25.define transparency. And list its types. The user of a distributed database system should not be required to know where the data are physically located nor how the data can be accessed at the specific local site. This characteristic is called data transparency. Types: fragmentation transparency Replication transparency Location transparency 26.What are the steps involved in data warehousing? 1.gathering of data 2.storage of data 3.Querying and data analysis support 27.Define clustering. It is a process of grouping similar points together in a single set. Types: 1.hierarchical clustering 2.agglomerative clustering 3.divisive clustering

20 28.What are the applications of OODB? CAD(computer aided design) Computer aided software engineering Multimedia and image databases Document/hypertext databases 29.Explain data classification. MAY/JUNE What are the advantages of data warehouse? MAY/JUNE Define a distributed DBMS. NOV/DEC How does the concept of an object in the object-oriented model differ from the concept of an entity in the ER model? NOV/DEC What is crawling and indexing the web? NOV/DEC What is relevance ranking? NOV/DEC Define Threats and risks. APR/MAY What is Association rule mining? APR/MAY Can we have more than one constructor in a class? If yes, explain the need for such a situation. NOV/DEC 2015 UNIT V PART-B 1.Explain about distributed databases and their characteristics, functions. MAY/JUNE Explain the advantages and disadvantages of distributed databases. MAY/JUNE differentiate between private and military organizations. 4.what is cryptography. and Explain different types of cryptography. APR/MAY What is database access control? Explain different types of database access control. APR/MAY explain the architecture of distributed database system. 7.explain various types of database privileges. NOV/DEC explain k-means algorithm with an example. APR/MAY what classification in data mining? How is it different from prediction? 10.explain relevance ranking in detail. 11.explain mechanism for specifying XML data. 12.explain briefly about OODB. NOV/DEC 2015 NOV/DEC explain data mining using association rule with an example. 14.Explain crawling and indexing the web briefly. NOV/DEC Differentiate between data and information retrieval. 16.Explain types of database security and database security issues. MAY/JUNE Discuss Apriori algorithm for mining association rules with an example. NOV/DEC Write short notes on distributed transactions. NOV/DEC 2014

21 19.Explain about discretionary access control based on granting and revoking privileges. NOV/DEC Write short notes on i)classification ii)clustering NOV/DEC Write short notes on data warehousing. NOV/DEC 2015 PART C 1. XML schema for an XML representation for relational schema. NOV/DEC Describe how to keep the bitmap upto date on record insertions and deletions. NOV/DEC Outline the benefit of the bitmap technique over free lists in searching for free space and in updating free space information. NOV/DEC 2016