Download database management system-assignment 2

PART – A
1. Design an ER diagram for an IT training group database that will meet the information
needs for its training program. Clearly indicate the entities, relationships and the key
constraints. The description of the environment is as follows:
The company has 12 instructors and can handle upto 100 trainees for each training session. The
company offers 5 Advanced technology courses, each of which is taught by a team of 2 or more
instructors Each instructor is assigned to a maximum of two teaching teams or may be assigned
to do research Each trainee undertakes one Advanced technology course per training session.
ANS:
company
Offers
handle
s
100
12
instructors
trainees
1
undertake
s
has
5
1
Advanced
technology courses
2
teaches
2. Identify at least 5 DBMS successfully running in market and compare their features.
ANS:
1. IBM's DB2- The IBM DB2 Enterprise Server Edition is a relational model database server developed
by IBM. It primarily runs on UNIX (namely AIX), Linux, IBM i, z/OS and Windows servers. DB2
also powers the different IBM InfoSphere Warehouse editions. Alongside DB2 is
another RDBMS: Informix, which was acquired by IBM in 2001. DB2 also lets you store some parts
of your code at the server instead of keeping all of it in your client application. This can have
performance and maintenance benefits.
There are features to protect data and to define relationships between data. As well, there are objectrelational features to create flexible, advanced applications. You can use some features in more than
one way. For example, constraints enable you to protect data and to define relationships between data
values. Here are some key DB2 features:
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
Constraints
User-defined types (UDTs) and large objects (LOBs)
User-defined functions (UDFs)
Triggers
Stored procedures
2. Oracle- The Oracle Database is an object-relational database management
system(ORDBMS) produced and marketed by Oracle Corporation.
Larry Ellison and his friends and former co-workers Bob Miner and Ed Oates started the consultancy
Software Development Laboratories (SDL) in 1977. SDL developed the original version of the
Oracle software. The name Oracle comes from the code-name of a CIA-funded project Ellison had
worked on while previously employed by Ampex.

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Scalability and Performance
Manageability
Backup and Recovery
High availability
Business Intelligence
Content Management
Security
Data integrity/Triggers
Information Integration Features
3. Microsoft SQL Server- Microsoft SQL Server is a relational model database server produced
by Microsoft. Its primary query languages are T-SQL and ANSI SQL.
 Database Mirroring
 Online Restore
 Online Indexing Operations
 Fast Recovery
 Standards-based Information Access SQL
 Server Management Studio
 Dedicated Administrator Connection
4. PostgreSQL- PostgreSQL is a powerful, open source object-relational database system. It has more
than 15 years of active development and a proven architecture that has earned it a strong reputation
for reliability, data integrity, and correctness. It runs on all major operating systems, including
Linux, UNIX (AIX, BSD, HP-UX, SGI IRIX, Mac OS X, Solaris, Tru64), and Windows. It is fully
ACID compliant, has full support for foreign keys, joins, views, triggers, and stored procedures (in
multiple languages). It includes most SQL:2008 data types, including INTEGER, NUMERIC,
BOOLEAN, CHAR, VARCHAR, DATE, INTERVAL, and TIMESTAMP. It also supports
storage of binary large objects, including pictures, sounds, or video. It has native programming
interfaces for C/C++, Java, .Net, Perl, Python, Ruby, Tcl, ODBC, among others, and exceptional
documentation.
5. MY SQL- MySQL is a relational database management system (RDBMS)[1] that runs as a server
providing multi-user access to a number of databases. MySQL is officially
pronounced /maɪˌɛskjuːˈɛl/ ("My S-Q-L"),[2] but is often also pronounced /maɪˈsiːkwəl/ ("My
Sequel"). It is named after developer Michael Widenius' daughter, My. The SQL phrase stands for
Structured Query Language.[3]
The MySQL development project has made its source code available under the terms of the GNU
General Public License, as well as under a variety ofproprietary agreements. MySQL was owned
and sponsored by a single for-profit firm, the Swedish company MySQL AB, now owned
by Oracle Corporation.
Data base
Maintainer
Release
date
Latest stable
version
Latest
release
date
22 Apr
2009
Software license
IBM
1983
9.7
Microsoft
1989
2008 R2
(v10.5)
MySQL
Sun Microsystems
1995-11
5.5.8
2010-12-15
GPL or Proprietary
Oracle
Oracle Corporation
1979-11
11g Release
2
2009-9
Proprietary
Global Development
Group
1989-6
9.0.2
2010-12-16
PostgreSQL licence
DB2
Microsoft
SQL Server
PostgreSQL
Proprietary
Proprietary
The operating systems the RDBMSes can run on:
Linux
BSD
UNIX
AmigaOS
Symbian
z/OS1
Yes
Mac OS
X
Yes
Yes
No
Yes
No
No
Yes
Microsoft
SQL Server
MySQL
Yes
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Oracle4
Yes
Yes
Yes
No
Yes
No
No
Yes
PostgreSQL
Yes
Yes
Yes
Yes
Yes
No
No
No
Data base
Windows
DB25
Information about what fundamental RDBMS features are implemented natively.
ACID
DB2
Yes
Referential
integrity
Yes
Transactions
Unicode
Interface
Yes
Yes
GUI & SQL
Microsoft
SQL Server
MySQL
Yes
Yes
Yes
Yes
GUI & SQL
Yes2
Yes2
Yes2
Yes
SQL
Oracle
Yes
Yes
Yes
Yes
API & GUI & SQL
PostgreSQL
Yes
Yes
Yes
Yes
GUI & SQL
3. How the various components of database management system interact for transaction
Processing.
ANS: The various components of database management system are:

DBMS Engine accepts logical requests from various other DBMS subsystems, converts them into
physical equivalents, and actually accesses the database and data dictionary as they exist on a
storage device.

Data Definition Subsystem helps the user create and maintain the data dictionary and define the
structure of the files in a database.

Data Manipulation Subsystem helps the user to add, change, and delete information in a database
and query it for valuable information. Software tools within the data manipulation subsystem are
most often the primary interface between user and the information contained in a database. It
allows the user to specify its logical information requirements.

Application Generation Subsystem contains facilities to help users develop transaction-intensive
applications. It usually requires that the user perform a detailed series of tasks to process a
transaction. It facilitates easy-to-use data entry screens, programming languages, and interfaces.

Data Administration Subsystem helps users manage the overall database environment by
providing facilities for backup and recovery, security management, query optimization,
concurrency control, and change management.
The transaction mechanism: A database transaction mechanism ideally guarantees ACID properties in
order to ensure data integrity despite concurrent user accesses (concurrency control), and faults (fault
tolerance). It also maintains the integrity of the data in the database. The DBMS can maintain the
integrity of the database by not allowing more than one user to update the same record at the same
time. The DBMS can help prevent duplicate records via unique index constraints; for example, no
two customers with the same customer numbers (key fields) can be entered into the database.
PART – B
4. Comment on the significance of administration of a database system. What are the various
functions associated with database administration?
ANS: A database administrator (DBA) is a person responsible for the design, implementation,
maintenance and repair of an organization's database. They are also known by the titles Database
Coordinator or Database Programmer, and are closely related to the Database Analyst, Database
Modeler, Programmer Analyst, and Systems Manager. The role includes the development and design
of database strategies, monitoring and improving database performance and capacity, and planning
for future expansion requirements. They may also plan, co-ordinate and implement security measures
to safeguard the database. Employing organizations may require that a database administrator have
a certification or degree for database.
Database administrator's activities can be listed as below:
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Transferring Data
Replicating Data
Maintaining database and ensuring its availability to users
Controlling privileges and permissions to database users
Monitoring database performance
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Database backup and recovery
Database security
5. Explain the concepts of Generalization and Specialization with examples.
ANS:
Generalization: The design process may also proceed in a bottom-up manner, in which multiple
entity sets are synthesized into a higher-level entity set on the basis of common features. The database
designer may have first identified a customer entity set with the attributes name, street, city, and
customer-id, and an employee entity set with the attributes name, street, city, employee-id, and salary.
There are similarities between the customer entity set and the employee entity set in the sense that
they have several attributes in common. This commonality can be expressed by generalization, which
is a containment relationship that exists between a higher-level entity set and one or more lower-level
entity sets. In our example, person is the higher-level entity set and customer and employee are
lower-level entity sets.
Specialization: An entity set may include subgroupings of entities that are distinct in some way from
other entities in the set. For instance, a subset of entities within an entity set may have attributes that
are not shared by all the entities in the entity set. The E-R model provides a means for representing
these distinctive entity groupings. Consider an entity set person, with attributes name, street, and city.
A person may be further classified as one of the following:
• customer
• employee
Each of these person types is described by a set of attributes that includes all the attributes of entity
set person plus possibly additional attributes. For example, customer entities may be described further
by the attribute customer-id, whereas employee entities may be described further by the attributes
employee-id and salary. The process of designating subgroupings within an entity set is called
specialization. The specialization of person allows us to distinguish among persons according to
whether they are employees or customers.