(1) define the fundamental concepts of the relational database model
Concept of a database is that of a
collection of records or pieces of information which is a structural
description of the type of facts held in database known as a schema.
Schema describe the objects that are represented in the database and
the relationships among them. There are ways of organizing a schema
modelling the database structure known as database models or data models. but nowadays, Relational model is commonly used which is all
information in the form of multiple related tables each consisting of
rows and columns. this model represents relationships by the use of
values common to more than one table. Hierarchy model and the network
model is use a more explicit representation of relationships.
(2) evaluate the advantages of the relational database model
- increased flexibility
- increased scalability and performance
- reduced information redundancy
- increased information integrity (quality)
- increased information security
INCREASED FLEXIBILITY
- good database that can handle changes quickly and easily
- physical view of information deals with the physical storage of information on a storage device such as a hard disk
- logical view of information focuses on how users logically access information to meet their particular business needs
INCREASED SCALABILITY & PERFORMANCE
- scalability refers to how well a system can adapt to increase demand
- performance measures how quickly a systems performs a certain process or transaction
REDUCED INFORMATION REDUNDANCY
- redundancy is the duplication of information, or storing the same information in multiple places
- occurs bcoz organizations frequently capture and store the same information in multiple locations.
- primary problem with redundant is that it is often inconsistent which makes it difficult to determine which values are most current or most accurate
INCREASED INFORMATION INTEGRITY (QUALITY)
- measures of the quality of information
- database environment, integrity constraints are rules that help ensure the quality of information
- two types of integrity:
(1) relational integrity constraints - enforce bacic & fundamental information based constraints
(2) business (critical integrity constraints)
- enforce business rules vital to an organization's success and often
require more insight and knowledge than relational integrity constraints
INCREASED INFORMATION SECURITY
- organizational asset
- as systems become increasingly complex and more available over the internet, security becomes an even bigger issue
- offer many security features including passwords access levels, and access controls
- password provide authentication of the user
(3) define the database management system (DBMS) and its relationship to a website
DBMS is software through which
users and application programs interact with a database. The user sends
requests to the DBMS and the DBMS performs the actual manipulation of
the information in the database. there are two primary ways that users
can interact with a DBMS, directly and indirectly.
(4) explain why an organization would want to integrate its database
by integrating its systems or
building connections between its many database, its allow the
organizations multiple system to automatically communicate by passing
information between the databases, eliminating the need for manual
information entry into multiple systems because after entering the
information once, the integrations send the information immediately to
all databases. the integrations not only enable the different
departments to share information, but have also dramatically increased
the quality of the information. without integrations, an organization
will,
1. spend considerable time entering the same information in multiple system
2. suffer from the low quality and inconsistency typically embedded in redundant information
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