Class Agenda – 09/03/2014

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Answer questions about course logisticsAccess Chapter 1 Grader Project and Quiz 1

remindersPresent computer data organizationExplore files, folders, and librariesDiscuss the different levels of software available to

manage data on a computer.Explore the functions of a DBMS vs. an operating

system to manage data.Discuss the relative data management capabilities

of a DBMS vs. a spreadsheet.Introduce Access

Course Learning Process

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Course objectivesVisualization methods; systems development processSystems development tools: Access and Excel

Methods to learn materialCourse lectures: concepts, exercises, questionsBook/MyITLab exercises:

Labs: in-class time to try out new and/or difficult Access and Excel skills/concepts

Outside of class: do book exercises not done in labsBook material:

Explanation, concepts, detailed descriptionMethods to assess learning (and hopefully learn more…)

Homework and projects: Apply instruction from tutorialsCreate simulated “real” applications

Help available

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Your books!!!!Online help via Access and ExcelGoogle (or other favorite search engine)Professor (Christina Hilfer)

Email: chilfer@unr.edu

Views of Computer Data Organization & Access

ConceptualI want to buy music

on iTunes. I want to see if that

shirt is available in blue in a size medium.

Physical

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Primary Storage/Main Memory

Processor

ALU

Secondary Storage/Disk

Data and Programs

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How does it work?

Primary Storage/Mai

n Memory

Processor

ALU

Secondary Storage/Disk

Data and Programs when they are not being processed

Data and Programs when they are being processed

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What is an operating system?Examples:

WindowsUnixMac OS XLinux

Definition: Set of software that manages a computer’s operations.

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What does an operating system do? Manage hardware and software resources:

Allocate main memory.Direct processor activities.Track all program activities.Manage network connections.Allocate secondary storage.Move data and programs from secondary

storage to main memory and back again.Manage users

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Moving data between primary and secondary storage

Secondary Storage/Disk

Primary storage/main memory

Operating System

MS Excel

Firefox

Photoshop

MS Word

Computer Data Organization Vocabulary

12 Bits

Bytes

Program Files Data Files

Database

Fields

Records

Windows Library: View

Folders

Organizing Files and Folders

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A file is a collection of bytes that has a name and is stored in a computer

A file can store a “program” or “data”Organize files by storing them in foldersDisks contain folders that hold files

USB drivesCompact discs (CDs)Digital video discs (DVDs)Hard disks

Each drive is assigned a letter

What types of data are stored on a computer?

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Video, pictures, audioEmailWeb pagesWord processing documentsPowerPoint-type presentationsStructured data: Pre-defined formats such

as employee, customer, student, registration data.

Understanding the Need for Organizing Files

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Windows (and all other operating systems) organizes folders and files in an hierarchy, or file system

Windows stores the folders and important files it needs to turn on the computer in its root directory

Folders stored within other folders are called subfolders

Developing Strategies for Organizing Files

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Developing Strategies for Organizing Files

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Type of disk you use to store files determines how you organize those files

Storing files on removable media allows you to use simpler organization

The larger the medium, the more levels of folders you should use

You should have a “backup”, or duplicate copy, of all filesDefinitely all data filesAll program files that you don’t have available

in other forms (downloads, other media)

Exploring Files, Folders, and Libraries

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Windows Explorer and the Computer window show the drives, folders, and files on your computerEach has a slightly different view

A folder window displays the files and subfolders in a folderDivided into two sections, called panes

Navigating to Your Data Files

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The file path is a notation that indicates a file’s location on your computerG:\FM\Tutorial\Map.pngG: is the drive nameFM is the top-level folder on drive GTutorial is a subfolder in the FM folderMap.png is the full filename with the file

extension

Managing Folders and Files

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Creating a folderIn the Navigation pane, click the drive or

folder in which you want to create a folderClick New folder on the toolbarType a name for the folder, and then press

the Enter key

Working with Folders and Files

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Moving and Copying Files and FoldersMoving a file removes it from its current location and places it in a

new location you specifyCopying places the file in both locations

Naming and Renaming FilesFilenames provide important information about the file, including

its contents and purposeMain part of the filenameFile extension

A filename extension identifies file type and indicates program in which file was created

Deleting Files and FoldersRecycle Bin is an area on your hard disk that holds deleted files

until you remove them permanentlyFiles removed from a network drive do not go to the Recycle Bin!

Working with Compressed Files

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Files stored in a compressed (zipped) folder take up less disk spaceAllows you to transfer files more quickly

Extracting a file creates an uncompressed copy of the file in a folder you specify, while the original file remains in the compressed folder

Compression programsWinZip7-Zip

What is a DBMS?A set of software that facilitates storage and

access of data on a computer.Designed to work with a specific operating

system.Examples from vendors.

Microsoft products: Access, FoxPro, SQL Server

Oracle products: Oracle, MySQL SAP: Sybase, HANAIBM products: Informix, DB2Open-ish: PostgreSQL

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What does a DBMS do?Data structure maintenance: add, delete,

change data objects. Data maintenance: add, delete, change

data.Data backup and recovery.Concurrency control.Data access (query) optimization. Security.Distributed data management.

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What does MS Access do?Data structure maintenance: add, delete,

change tables for data storage. Data maintenance: add, delete, change

data in tables.Provide user-friendly tools for data access.

Forms.Reports.Integration with other software such as Excel.

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Why do we store data in a database?

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To protect the “integrity” of the data.Make data accurate.Reduce data redundancy.

To make data more accessible.Enhance flexibility of data access methods.Improve speed of data access.

To make an application more adaptable.Provide more flexibility in application

development.Decrease dependence on a given visualization

method.

What other software is available for data storage?

Word processingSpreadsheetsApplication programs

Examples: TurboTax, QuickBooksData storage: files, or enhanced file structuresSome application programs rely on a DBMS

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Decision Issue

Spreadsheet (Excel)

Database (Access)

Ability to maintain accurate data

Limited. Completely dependent on user for accurate input.

Excellent. Many filters/constraints available to protect data accuracy.

Ease of showing data in different formats

Limited. Can make small color changes to basic spreadsheet.

Excellent. Very flexible. Data entered once can be viewed in many different formats.

Ease of doing calculations

Excellent. Statistics, financial functions available.

Limited. Can do calculations, but only basic math.

Difficulty of learning/using product

Excellent. Easy to learn.

Difficult to learn.

Necessity for pre-planning

Not much planning required.

Must plan/design the database in advance.

Overview of MS Access

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Data Management Software Has the following objects:

Tables: Object to store data. This is the only data storage object in Access.

Queries: Object to view data stored in tables. Can be used to filter data, reformat data, create calculations, create aggregations, create summarizations.

Forms: Object to enter data into a table in user friendly format. Also used to view data in a nice format on a screen.

Reports: Object to view data in a nice format on paper.

Database Vocabulary- 1Table: A two-dimensional database object

used to store data.Row: One “entry” of data within the table.

Must have a primary key that has a different value than all other rows of data within the table

Column: A field used to store data. Must have a single data type.

Cell: An intersection of a row and column. Can only have one data type and one value.

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Database Vocabulary- 2Entity (when implemented it is called a

“table”): A person, place, or thing about which we store data. Example is a Customer for Belmont Landscapes.

Entity instance(also called a “record” or “row”): One instance of an entity that includes all data stored about that instance. Example is “Anthony Rodriquez row” for Belmont.

Attribute (also called a “field” or “column”): A characteristic of the entity about which we store data. Examples are Company, FirstName, Lastname for a Customer entity.

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