database
Organized collection of data
database management system (DBMS)
-Group of programs that manipulate the database
-provide an inferface between the database and its users and other applications
database administrator (DBA)
skilled IS professional who directs all activities related to an organizations database
Works with users to decide the content of the database
works with programmers as they build applications to ensure that their programs comply with database management
Data Management
-Without data and the ability to proccess it, an organization could not successfully complete most business activities
-data consists of raw facts
-to transform data into useful information, it must first be organized in a meaningful way
Bit (a binary digit)
-circuit that is either on or off.
Hierarchy of Data
Byte
-Typicall made up of eight bits.
Hierarchy of Data
Character
-Basic building block of information.
Hierarchy of Data
Field
-Name, number, or combination of characters that descrive an aspect of a business object or activity
Hierarchy of Data
Record
Collection of related data fields.
Hierarchy of Data
File
Collection of related records
Hierarchy of Data
Database
Collection of integrated and related files
Hierarchy of Data
Hierarchy of Data
Bits, bytes, characters, fields, records, files, and databases.
Hierarchy of Data
Entity
A person, place, or thing for which data is collected, stored, and maintained.
Data Entities, Attributes, and Keys.
attribute
Characteristics of an entity
Data Entities, Attributes, and Keys.
Data item
Specific value of an attribute
Data Entities, Attributes, and Keys.
Key
Field of rest of fields in a record that is used to identify the record
an attribute that can be used to uniquely identify every instance of an entity
a set of fields to identify an entity would be using first name and last name combined to find the recor
Primary key
field or set of fields that uniquely identifies the record.
A foreign key is what links the primary key from one table set to another table set.
Traditional approach to data management
Each distinct operational system used data files dedicated to that system
The database approach.
Database approach to data management
Pool of related data is shared by multiple application programs
The database approach.
When building a database, an organization must consider
Content - what data should be collected and at what cost?
if sensitive, personal data is leaked, it can cause someone to pay out money in law suits, that data is negative data.
postive data- ex. information gathered about an organization and sold to the o
Data Centers Physical Organization info (5/5)
Consist of warehouses filled with row upon row of server racks and powerful cooling systems.
Data Center
Data Centers Physical Organization info (1/5)
Climate controlled building or set of buildings that house databases servers and the systems that deliver mission critical information and services.
Data Center
Data Centers Physical Organization info (2/5)
Many organizations now use large shipping containers packed with racks of servers and cooled to easily connect and set up
Data Center
Data Centers Physical Organization info (3/5)
Businesses and technology vendors working to develop green data centers that run more efficiently and require less energy for processing and cooling
Data Center
Data Centers Physical Organization info (4/5)
backup and security procedures for data centers can be a conern
Data Center
Data model
Diagram of data entities and their relationships
Data Modeling.
Enterprise data modeling
starts by investigating the general data and information needs of the organization at the strategic level.
Data Modeling.
Entity-relationship (ER) Diagrams
Data models that use basic graphical symbols to show the organization of and relationships between data.
Just shows entities, and relationships.
Data Modeling.
Relational database model
Describes data using a standard tabular format
Each row of a table represents a data entity (record)
columns of the table represent attributes (fields)
The domain is the range of allowable values for data attributes
Relational database model
Manipulating data
Selecting - eliminates rows according to certain criteria
Projecting - eliminates columns in a table
Joining - combines two or more tables
Linking - manipulating two or more tables that share at least one common data attribute.
Relational database model
Data cleanup
Process of looking for and fixing inconsistencies to ensure that data is accurate and complete
Databases normalization is often used to clean up problems with data
Update- when you update some information in an entity, you have to update all of the other
Database management systems
Creating and implemeting the right database system ensure that the database will support both business activities and goals
Capabilities and types of databases systems vary considerably
Overview of database types
Flat File - a simple database probram whos records have no relationship to one another
Single user
- only one person can use the database at a time. Ex: access, filemaker pro, InfoPath
Multiple user
-allow dozens or hundreds of people to access the same d
Providing a user view
Schema
-used to describe the entire database
-can be part of the database or a separate schema file
DBMS
-can reference a schema to find where to access the requested data in relation to another piece of data
Data definition language (DDL)
-Colleciton of instructions and commands used to define and describe data and relationships in a specific database
-a set of commands used to construct the database.
-allows databases creator to describe data and relationships that are to be contained in
Data dictionary
detailed description of all the data used in the database
Creating and Modifying the Database
Storing and retrieving data
When an application program needs data it requests the data through the DBMS
Requesting the data through the DBMS is a process called querying
Concurrency controls deals with the situation in which two or more users or applications need to access the same
Query by example (QBE)
is a visual approach to developing database queries or requests.
Manipulating Data and Generating Reports
Data manipulation language (DML)
Commands that manipulate the data in a database
Once a database has been set up and loaded with data, it can produce report, documents, and other outputs.
Structured query language (SQL)
adopted by the American National Standards Institute (ANSI) as the standard query language for relational databases
Manipulating Data and Generating Reports
DBMSs
can act as front-end or back-end applications
Direct access is through the DBMS
Front-end applications interact directly with people to retrieve and use information from the Database
-back-end applications interact with other programs or applications to r
Database applications
Todays database applications manipulate the content of a database to produce useful information
Common manipulations:
searching, filtering, synthesizing, and assimilating data contained in a database using a number of database applications
Big data applications
deals with large amounts of unstructured data from the internet, photos, video, audio, social, networks, and sensors.
deals with large amounts of unstructured data to analyse trends
IE. netflix uses this to come up with suggesstions of what to watch next
linking the company database to the internet and mobile devices
Security always a concern when linking a database to the internet
Semantic Web
- developing a seamless integration of traditional databases with the internet
Metadata - data that defines data items
-provides metadata with all web content using technology
Data warehouse
Database that holds business information from many sources in the enterprise
Data mart
subset of a data warehouse
Data mining
information-analysis tool that involves the automated discovery of patterns and relationships in a data warehouse.
Data mining: Predictive analysis
-form of data mining that combines historical data with assumptions about future conditions to predict outcomes of events.
- used by retailers to upgrade occasional customer into frequent purchasers
-used to predict future sales up to a year in the future
Business intelligence
Involves gathering enough of the right information
-in a timely manner and usable form and analyzing it to ahve a positive impact on business strategy, tactics, or operations
corporate espionage is illegal, acquiring public knowledge and data is legal.
Competitive intelligence
Limited to information about competitors and the ways that knowledge affects strategy, tactics, and operations.
counter intelligence
-steps organization takes to protect information sought by "hostile" intelligence gathers
-protecting against corporate espionage
Data loss prevention DLP
-refers to the systems designed to lock down data within an organization
-powerful tool for counter intelligence
-a necessity in complying with government regulations that require companies to safeguard private customer data.
Distributed database
Database in which the data may be spread across several smaller databaqses connected via telecommunications devices
-gives corporations more flexibility in how databases are organized and used
used to increase efficiency, effectiveness
Replicated database
holds a duplicate set of frequently used data
online analytical processing (OLAP)
allows users to explore data from a number of perspectives. Provides top-down, query-driven data analysis
Data Mining VS OLAP
Purpose:
Both supports data analysis and decision making
Type of analysis supported:
OLAP - top down query-driven data analysis
Data Mining - Bottom up discovery-driven daya analysis
Skills required of user:
OLAP: must be very knowledgeable of the data an
Object- relational Database management systems (ORDBMS)
Provides the ability for third parties to add new data types and operations to the databases
Object oriented database management system (OODBMS)
stores both data and its processing instructions
Uses an object oriented database management system OODBMS to provide a user interface and connections to other programs.
visual databases
used to store images of charge slips, X rays, vital records
can be stored in some object-relational databases or special-purpose database systems
Spatial data technology
using database to store and access data according to the locations it describes
Summary (informational overview of Ch. 5.)
data is one of the most valuable resources that a firm possesses
an entity is an object for which data is collected, stored, and maintained
traditional file oriented applications are often characterized by program data dependence
the relational model plac
Database as a service DaaS
emerging database system
database administration is provided by the service provider
the database is stored on a service providers servers and accessed by the client over a network.
NoSQL DBMS
can handle data that does not fit into tables required by traditional relational databases
increasing in popularity.