Chapter 4 Questions
Fudamentals of Information Systems
Complete the following sentences:
 Character is a single alphabetic, numeric or other symbol.
 Field or data item is a grouping of related characters.
 Field represents an attribute (a characteristic or quality) of some entity
(object, person, place or event).
 Record is grouping of all the fields used to describe the attributes of an
entity.
 File or table is a group of related records.
 Database is an integrated collection of logically related data elements.
 Explain the Electric Utility Database diagram shown below.
 State the Database structures types.
 In Hierarchical Database structure, records arranged in tree-like structure
and relationships are one-to-many.
 Network Database structures are used in some mainframe DBMS packages
and relationships are Many-to-many.
 Relational Structure is the most widely used structure.
 In Relational Database Structure data elements are viewed as being stored
in tables.
 Examples of Relational Database operations are select, join, and project.
 Relational Database operation Select is used to create a subset of records
that meet a stated criterion.
 Relational Database operation Join is used to combine two or more tables
temporarily to form a one big table.
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 Relational Database operation Project is used to create a subset of columns
in a table.
 Multidimensional database structure uses multidimensional structures to
organize data and data elements are viewed as being in cubes. It is popular
for analytical databases that support Online Analytical Processing (OLAP).
 An object consists of data values describing the attributes of an entity, and
operations that can be performed on the data.
 Encapsulation combines data and operations.
 In inheritance, new objects can be created by replicated some or all of the
characteristics of parent objects.
 Object-oriented database structure supports complex data types as graphic
images, video clips, and web pages.
 Databases that organize and store data as objects are called Object-oriented
databases.
 Hierarchical database structure worked for structured routine transaction
processing and can’t handle many-to-many relationships.
 Network database structure is more flexible than hierarchical structure and
unable to handle ad hoc requests.
 Relational database structure easily respond to ad hoc requests, easier to
work with and maintain, and not as efficient or quick as hierarchical or
network structures.
 Data Definition Language (DDL) used to develop and specify the data
contents, relationships and structure, and modify the database
specifications when necessary. These specifications are stored in a data
dictionary.
 Data dictionary is a data base catalog containing metadata.
 Metadata is data about data.
 Enterprise model defines basic business process of the enterprise. It is
Defined by DBAs and designers with end users.
 Entity Relationship Diagram (ERD) is a common tool for Data Modeling.
 Data dictionary defines and catalogs the data elements and data
relationships in an organization’s database.
 A schema is an overall logical view of the relationships among the data
elements in a database.
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 A subschema is a logical view of the data relationships needed to support
specific end user application programs that will access that database.
 In database design process the name subschema is given to logical view of
specific end user.
 State the types of databases.
 Operational databases Store detailed data to support business processes
and operations.
 Examples of operational databases are customer database, inventory
database and human resource database.
 Distributed databases consists of copies or parts of databases on servers at a
variety of locations.
 Distributed Database replication is very complex. Its steps are: Look at each
distributed database and find changes - Apply changes to each distributed
database.
 Distributed database duplication is easier than replication. It basically
identifies one database as a master and then duplicates that database at a
prescribed time after hours.
 In distributed databases the name duplication is given when applying one of
the databases as master and then modifying other databases after hours in
all locations.
 External databases are databases available for a fee from commercial online
services or for free from World Wide Web.
 Examples of external databases are statistical databanks, bibliographic and
full text databases.
 Hypermedia database consists of hyperlinked pages of multimedia.
 Data Warehouse Stores data that has been extracted from the operational,
external and other databases. Data has been cleaned, transformed and
cataloged.
 Data Warehouses are used by managers and professionals for data mining,
online analytical processing, business analysis, market research, and
decision support.
 Data mart is a subset of warehouse for specific use of department.
 In data warehouse, data are analyzed to reveal hidden patterns and trends.
 In traditional file processing systems, data stored in independent files.
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 Problems of traditional file processing systems are: data redundancy, lack of
data integration, data dependence, and lack of data integrity or
standardization.
 In traditional file processing systems, data dependence means that files,
storage devices, and software are dependent on each other.
 Database management Approach consolidate data into databases that can
be accessed by different programs using a database management system
(DBMS).
 Database management system (DBMS) serves as interface between users
and databases.
 Explain the operation of Traditional File Processing systems using the
diagram shown below.
 Explain the operation of Database Management Systems using the diagram
shown below.
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 The Database Management System controls the creation, maintenance, and
use of the databases of an organization and its end users.
 End users use a DBMS by asking for information via a query or a report
generator.
 SQL (Structured Query Language) an international standard query language.
 Graphical Queries are point-and-click query methods.
 Natural Queries are similar to conversational English.
 The report generator feature allows you to quickly specify a report format
for information you want presented as a report.
 Updating database to reflect new business transactions such as a new sale
known as database maintenance.
 Database maintenance is done by transaction processing systems with
support of DBMS.
 Application development is the Use of DBMS software development tools to
develop custom application programs.
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