Information Systems For Business and BeyondChapter 4Data a.docx
- 1. Information Systems For Business and Beyond Chapter 4 Data and Databases IST 5500
- 3. 1 Objectives Describe differences between data, info & knowledge Define database & identify steps to create one Describe role of a database management system Describe characteristics of a data warehouse; and Define data mining & describe its role in an organization 2
- 4. Data, Information & Knowledge Data: raw bits & pieces of info Quantitative or qualitative Data alone not useful Needs context to be information Aggregate & analyze: knowledge Knowledge used for decisions Wisdom includes experience! NOTE: We will not be discussing older, hierarchical databases during this class Databases Relational database most popular Limit our discussion to them Examples: MS Access, MySQL & Oracle Data organized into one or more tables Each table contains set of fields A record is one instance of a set of fields Tables related by one or more fields: primary key Database Design Needs, requirements & goals?
- 5. Define data requiring tracking Determine tables needed Specifically which fields Data to which they will relate Establish primary key (unique) Normalize: avoid duplicates & achieve flexibility Designing a Database Example: a university wants to create an information system to track participation in student clubs Goal to give insight into how university funds clubs Track number of club members & club activeness Must keep track of the clubs, members & events Following tables needed: Clubs: club name, club president, short description of club Students: student name, e-mail, year of birth Memberships: correlates students with clubs, any given student can join multiple clubs Events: when clubs meet & attendance Designing a Database continued Primary key must be selected for each table to create a relationship unique identifier for each record in a table Designing a Database Table Details
- 6. Designing a Database Table Details cont. Designing a Database continued Normalization Design database in a way that: reduces duplication of data between tables gives table as much flexibility as possible Purpose of creating Memberships table separate from Students & Clubs tables Makes it simple to change design without major modifications to existing structure Data Types Each field in a database table needs a data type Text, Number, Yes/No, Date/Time, Currency, Object, etc. Importance of properly defined data types tells database what functions can be performed proper amount of storage space is allocated for data Data Types: Assigned by Fields Text – generally under 256 characters Numbers* – usually different types Yes/No – decisions (*special type) Date/Time – formats (*special type) Currency – types (*special type)
- 7. Paragraphs - allows text over 256 Objects – images, music, etc. Database Tables 1NF (1st normal form) Database Demonstration Time permitting: Microsoft Access Structured Query Language (SQL) Work with relational databases Simple requests or complex tasks Example creates list of number students in each club, listing club name & number of members: SQL: What can it do? Execute queries against a database Retrieve data from a database Insert, update & delete records Create new databases new tables in a database stored procedures (transactions)
- 8. views in a database Set permissions on tables, procedures, and views Other Types of Databases Relational database model is most used today Hierarchical database model popular in the 1960s & 1970s connected data together in hierarchy, allowing for parent/child relationships Document-centric model allowed for a more unstructured data storage by placing data into “documents” that could then be manipulated NoSQL (“not only SQL”) Arose from need to solve problem of large-scale databases spread over several servers or even across world Can work with data in a looser way (no need for locks), allowing for a more unstructured environment, communicating changes to the data over time to all the servers that are part of the database Database Management Systems Software packages providing for: Database creation Reading/querying Changing/updating Add to or removing Single user: MS Access & OpenOffice Enterprise Databases Multi-user Networked
- 9. Metadata: Data about Data> Example Enterprise Databases Databases must be accessible to more than one person at a time Relational enterprise database packages built to support two, ten, or even a million people Relational databases have a scaling issue Big Data such massively large data sets that conventional database tools do not have the processing power to analyze them understanding best tools & techniques to manage & analyze these large data sets is a problem that governments & businesses alike are trying to solve Data Warehouse Typically a separate database Used analyze large amounts of data Should be designed such that: uses non-operational data data is time-variant (time stamped) data is standardized data is standardized
- 10. Data Warehouse continued: Data mining Online Analytical processing (OLAP) Purpose: building business intelligence Data Warehouse continued: Top-down DW Data Warehouse Benefits Process of developing data warehouse forces organization to better understand data it is currently collecting and, equally important, what data is not being collected Provides centralized view of all data being collected across enterprise; provides means for determining data consistency Once all data identified as consistent, an organization can generate one version of the truth. IMPORTANT when company wants to report consistent statistics about itself, such as revenue or number of employees Snapshots of data can be taken over time, creating historical record of data, allowing for trend analysis Provides tools to combine data, which can provide new information & analysis
- 11. Data Mining Process of analyzing data to find previously unknown trends, patterns & associations to make better decisions Accomplished thru automated means against extremely large data sets, e.i., data warehouse market basket analysis Beer and diapers Target pregnancy prediction Privacy Concerns Becoming easier than ever to take data from disparate sources and combine them to do new forms of analysis Business Intelligence & Business Analytics Business intelligence process that organizations use to take collected data & analyze hoping to obtain competitive advantage Business analytics is use of internal company data to improve business processes & practices Knowledge Management (KM) All companies accumulate knowledge over course of their existence Much knowledge is not written down; instead, stored inside heads of employees KM, process of formalizing capture, indexing & storing of company’s knowledge to benefit from experiences & insights that company has captured during its existence Milliken Carpet Maplewood Test Lab Customer Data
- 12. Procedures Privacy Concerns Regarding databases: Security controlled access Access limited by login We’ll discuss further in Chapter 12 Software QA: Data Owners Evaluate SQA classification (i.e. criticality) Develops controls to assure data integrity Evaluates and dispositions data error notices Assures appropriate disaster prevention & recovery SQA: Disaster Recovery Software/data owners include disaster recovery in requirements specs or SQA Plan At a minimum, considers prioritization & recovery of important/critical software systems & data Plans/procedures documented Periodically tested Evaluated when there are changes to the software, the data or the operating environment Normally, software & data owners are the same person or organization, but they do not have to be
- 13. Group Discussion 1: Your group has been asked to determine the requirements for designing a database for your Junior Baseball League. List the pieces of information that you need to acquire from stakeholders in order to minimize shortcomings and iterations during the preliminary design phase. Form into groups of 4 or 5 Elect a spokesperson Be prepared to present to class Group Discussion 2: You are going to develop a new database. Your group will be assigned one of the following topics: Collection of music files Collection of digital photographs Coin collection or Stamp collection Large book collection Develop a list of fields that should be included in your database; indicate the type of field; and determine which would be a good primary key Form into groups of 4 or 5 Elect a spokesperson Be prepared to present to class
- 14. Group Discussion 3: Handout Chapter 4 Analyzing the Current Database Groups should work together following the instructions listed on the handout. Form into groups of 4 or 5 Elect a spokesperson Be prepared to present to class Summary Described differences between data, info & knowledge Defined database & identify steps to create one Described role of a database management system Described characteristics of a data warehouse & Defined data mining & describe its role in an organization Questions