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Data Resource Management
Section 1: “Technical Foundations of Database Management”
CHAPTER 5
Lecture-7/ T. Nouf Almujally
Outline
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Section 1: Technical Foundations of Database
Management
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Database Management
Fundamental Data Concepts
Database Structures
Database Development
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Data planning and Database Design (not required)
Section 1
Technical Foundations of Database Management
Database Management
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Data are a vital organizational resource that need to be
managed like other important business assets.
Today's business enterprise cannot succeed without quality
data about their internal operations and external environment.
In all information systems, data resources must be organized
and structured in some logical manner so that they can be
accessed easily, processed efficiently, retrieved quickly, and
managed effectively.
Database provide a logical organization method and easy
access to the data stored in it.
Logical Data Elements
• Data may be logically organized into:
Logical Data Elements
Character
•A single
alphabetic,
numeric, or
other symbol
Field
(data item)
•Consists of a
grouping of
related
characters.
•Represents an
attribute
(characteristic)
of some entity
(object, person,
place, event)
•Examples…
salary, job title
Record
•Grouping of all
the fields used to
describe the
attributes of an
entity
•Example… payroll
records with
name, SSN, pay
rate
•Primary Key.
File
(table, flat file)
•Group of related
records
Database
•Integrated
collection of
logically related
data elements
•It consolidates
records
previously stored
in separate files
into a common
pool of data
elements that
provides data for
many
applications
Fundamental Data Concepts
Fundamental Data Concepts
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The data stored in a database are independent of
the application programs using them and of the type
of storage devices on which they are stored.
Databases contain data elements describing entities
and relationships among entities.
Electric Utility Database
Business
applications
that access the
data in the DB
Database Structures
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The relationships among the many individual data
elements stored in databases are based on one of
several logical data structures, or models.
Database management system (DBMS) packages are
designed to use a specific data structure to provide end
users with quick, easy access to information stored in
databases.
Five fundamental database structures:
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Hierarchical , network , relational, object-oriented and
multidimensional models.
Common Database Structures: Hierarchical
Root Element
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Early mainframe DBMS packages used this structure.
Records arranged in a hierarchy or tree-like structure
Relationships are one-to-many
Common Database Structures: Network
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Can represent more complex logical relationships and is still
used by mainframe DBMS packages.
Many-to-many relationships among records.
Common Database Structures: Relational
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Most widely used structure
• Used by microcomputer DBMS packages, as well as by most midrange and
mainframe systems.
• Data elements are stored in tables (sometimes referred to as relations).
• Row represents a record; column is a field.
• DBMS packages based on relational model can relate data in one table with
data in another, if both tables share a common data element.
Common Database Structures: Relational
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A lot of commercial products exist to create and
manage relational models:
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Mainframe relational DB applications:
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Oracle10g from Oracle
DB2 from IBM
Midrange DB applications:
• SQL Server from Microsoft.
The most commonly used DB application for the PC is
Microsoft Access.
Common Database Structures: Multidimensional
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Variation of relational model that uses
multidimensional structures to organize data and
express the relationships between them.
Data elements are viewed as being in cubes. Each side of the
cube is considered a dimension of the data.
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Each dimension represent a different category.
Have become the most popular database structure for the
analytical databases that support Online Analytical Processing
(OLAP) applications, in which fast answers to complex business
quires are expected.
Multidimensional Database Structures
Multidimensional Database Structures
Multidimensional Model
Common Database Structures: Object-Oriented
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the object-oriented model is considered one of the key technologies of a new
generation of multimedia Web-based applications.
An object consists of
• Data values describing the attributes of an entity
• Operations that can be performed on the data
Encapsulation Combine data and operations
Inheritance  New objects can be created by replicating some or all of the
characteristics of parent objects
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OODBMS now is popular in CAD and in multimedia Web-based applications.
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Supports complex data types more efficiently than relational databases
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Examples: graphic images, video clips, web pages
Common Database Structures: Object-Oriented
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major relational DBMS vendors add object-oriented modules to their relational
software.
Examples include multimedia object extensions to IBM’s DB2 and Oracle’s objectbased “cartridges” for Oracle.
Evaluation of Database Structures
Hierarchical
- Was for DB’s used for
the structured, routine
types of transaction
processing of many
business in the early
years of data
processing and
computing.
- Can’t handle manyto-many relationship
Network
Relational
- More flexible than
hierarchical
- Easily responds to ad
hoc requests
- Unable to handle ad
hoc requests
- Easier to work with &
maintain
-Can't process large
amounts of bus.
Transactions as efficient
or quick as hierarchical
or network
- can’t process complex
applications as objectoriented models.
- Ex: Oracle, DB2, Access
, Lotus Approach
Con.
Object-Oriented
Multidimensional
-Can process complex,
high volume
applications.
The use of this model
is growing steadily.
- The use of this model
is growing steadily.
- Play a great role in
web-based
applications.
- Play a great role in
OLAP applications.
Database Development
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Database management package like Microsoft Access or Lotus
Approach allow end users to develop the databases they need easily.
Large organizations usually place control of enterprise database
development in the hands of (DBA) and other database specialists.
Database Development
Database Administrator (DBA)
In charge of enterprise-wide database development
Improves integrity and security of organizational databases
Uses Data Definition Language (DDL) in DBMS to develop and
specify data content, relationships, and structure
This information is then stored in a database of data definitions and
specifications called a data dictionary or metadata repository
which is managed by the DBA
Data Dictionary
Data
Dictionary
Directory holds information about the database and the
data that it stores (data about data = metadata)
Relies on specialized software component to manage a
database of data definitions
Names and descriptions of all types of data records and
their interrelationships
Requirements for end users’ access and use of
applications
Contains
information
on…
Database maintenance
Security
Data Dictionary
Database Development
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Developing a large DB of complex data types can be a
complicated task.
Database administrator and the database design analyst
work with end users and system analysts to model the business
processes and the data they require. Then they determine:
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What data definitions should be included in the DB.
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What relationships should exist among the data elements.
Questions ..
Resources ..
Read from Chapter 5 (Section 1)