A database system that incorporates all the important object-oriented concepts that are

includes Abstract Data Types (Class definition, provides extension to complex attribute
types) Encapsulation (Data and functions combine into single unit) Inheritance (Transfer
the certain attribute from its parent or root) Method Overloading (one function can work
differently based on input parameter).
Advantages:
1. Semantics (Structure) contents added.
2. Visual representation includes semantic content.
3. Inheritance promotes data integrity.
4. Class, Overloading, encapsulation and inheritance are available.
Disadvantages:
1. Slow development of standards caused vendors to supply their own enhancements, thus
eliminating a widely accepted standards.
2. It is a complex navigational system.
3. There is a steep learning curve.
4. High system overhead slows transactions.
5. Required more memory to represent object.
SQL:
Structured Query Language (SQL) is a standard computer language for relational database
management and data manipulation. SQL is used to query, insert, update and modify data.
Most relational database support SQL, which is an added benefit for database administrators
(DBAs), as they are often required to support database across several different platform.
Data Definition Language (DDL): - A data definition language (DDL) is a language used to
create and modify the structure of database objects in a database. These database objects
include views, schemas, tables, indexes etc.
Data Manipulation Language (DML): - DML is a family of query languages including
commands permitting users to manipulate data in a database. This manipulation involves
inserting data into database tables, retrieving existing data, deleting data from existing tables
and modifying existing data.
Database Administrator:
One of the main reasons for using DBMS is to have central control of both the data and the
programs that access those data. A person who has such central control over the system is
called a database administrator (DBA).
The function of DBA:
1. Schema Definition:- The DBA creates the original database schema by executing a set of
data definition statements in the DDL.
2. Storage structure and access-method definition.
3. Schema and physical-organization modification:- The DBA carries out changes to the
schema and physical organization to reflect the changing needs of the organization, or to
alter the physical organization to improve performance.
4. Granting of authorization for data access: - By granting different types of
authorization, the database administrator can regulate which parts of the database various
users can access. The authorization information is kept in a special system structure that the
database system consults whenever someone attempts to access the data in the system.
5. Routine maintenance:- Examples of the database administrator’s routine maintenance
activities are:
 Periodically backing up the database, either onto tapes or onto remote servers, to
prevent loss of data in case of disasters such as flooding.
 Ensuring that enough free disk space is available for normal operations, and upgrading
disk space as required.
 Monitoring jobs running on the database and ensuring that performance is not
degraded by very expensive tasks submitted by some users.
6. Data Security:- DBA protect from malicious attempts (unauthorized user) to steal (view)
or modify data.
7. Secrecy:- Users should not be able to see things they are not supposed to.
Example: A student can’t see other student’s grades.
8. Integrity:- Users should not be able to modify things they are not supposed to.
Example:- Only instructor can assign internal marks.
9. Availability:- Users should be able to see and modify things they are allowed to.
There are three main security objectives. First, information should not be disclosed to
unauthorized users (secrecy). Second, only authorized users should be allowed to modify
data (Integrity). Third, authorized users should not be denied access (availability)
Authentication:-
Authentication is the process of confirming that a user logs in only in accordance with the
rights to perform the activities he is authorized to perform. User authentication can be
performed at operating system level or database level itself.
Authorization is the process of giving someone permission to do something. In multi-user
database management systems, a database administrator defines some privileges. Based on
those privilege, users are allowed/disallowed to access the resources of database.
Database Design is the process of producing a detailed data model of a database. This data
model contains all the needed logical and physical design choices and physical storage
parameters needed to generate a design in a data definition language, which can be used to
create a database. A fully attributed data model contains detailed attributes for each entity.
The process of doing database design generally consists of a number of steps which will be
carried out by the database designer. Usually, the designer must:
 Determine the data to be stored in the database
 Determine the relationships between the different data elements.
 Apply to a logical structure upon the data on the basis of these relationship.
Data warehouse (DW)
 DW are centralized data repositories that integrates data from various transactional,
legacy, or external systems, applications and sources.
 The data warehouse provides an environment separate from the operational systems
and is completely designed for decision-support, analytical-reporting, ad-hoc queries
and data mining.
 This isolation and optimization enables queries to be performed without any impact on
the systems that support the business’s primary transactions (i.e. transactional and
operational systems)

The data characteristics/Features of Data Warehouse are:

 Subject-Oriented
 Time-Variant
 Non-Volatile
 Integrated
Advantages of DW (Data Warehouse)
 Allows end users to perform extensive analysis
 Allows a consolidated view of corporate data
 Better and more timely information
 Enhancement of system performance
 Simplification of data access
  Enhance business knowledge
 Present competitive advantage
 Help in reforming business processes
Disadvantages of DW (Data Warehouse)
 Data warehouse are not the optimal environment for unstructured data. Because data
must be extracted, transformed and loaded into the warehouse.
 Data warehouse can have high maintenance costs.
 Data warehouse can get outdated relatively quickly
 Required skilled person to generate DW
 Longer time to developed
Data Mart:
A data mart is a subset of a data in which a summarized or highly focused portion of the
organization’s data is placed in a separate database for a specific population of users. For
example, a company might develop marketing and sales data marts to deal with customer
information. A data mart typically focuses on a single subject area or line of business, so it
usually can be constructed more rapidly and at lower cost than an enterprise-wide data
warehouse.
Data Mining:
 Data Mining is defined as extracting the information from the huge set of data. In
words, data mining is mining the knowledge from data.
 It can find out hidden patterns and relationships in large databases and deducing rules
from them to predict future behavior. The patterns and rules are used to guide decision
making and forecast the effect of those decisions.
 The types of information obtainable from data mining include association, sequences,
classifications, clusters, and forecasts.

Association: Determines occurrences linked to a single event.

Sequences: Determine events that are linked over time.
Classification: Discover characteristics of customers and make predictions about their
behavior.
Clustering: Discover groups within data.
Forecasting: Use existing values to forecast what other values will be.

Assignments:
1. Define Database and DBMS with their advantages and disadvantages.
2. Explain the different database models with their merits and demerits.
3. Write down the steps to design the database with example.
4. What do you mean by data security? Explain authorization and authentication with
example.
5. Define Data Warehouse with its pros and cons.
6. What is data mart? Differentiate between data warehousing and data mart.
7. Who is DBA? Write the responsibilities of DBA.
8. What is data mining? Explain the data mining process.
9. What is SQL? Explain the types of Query Languages.
10. What is flat file? Discuss its limitation.