Database & Database Designs 1

Welcome to Databases Our goal is to have a basic understanding of databases Resources: ◦ Slides ◦ In Class Activities ◦ No textbook required ◦ Videos 2

Recommended Reading Only if you want to get a deeper understanding: Database Design for Mere Mortals, Hernandez, 1997, Addison Wesley ISBN:

Why Learn Databases? STORE INFORMATION Information is a valuable commodity Information is used for marketing and BI (Business Information) Used by all kinds of businesses Access to good information (if properly done) Market to individuals creatively, rather than “mass mailing”, more customized (Business Intelligence) 4

Database Terms DATA ◦ From dictionary.reference.com, “INDIVIDUAL facts, statistics, or items of information”. ◦ NEVER “CONTRIVED” OR “DERIVED” VALUES 5

Database Terms DATASET According to Dictionary.com, a database is “a comprehensive collection of related data organized for convenient access, generally in a computer.”data usually refers to data selected and arranged in rows and columns ◦ for processing by statistical software. The data might have come from a database, but it might not Simply put, an: “ORGANIZED COLLECTION OF DATA.” 6

Database Terms DATABASE ◦ A COMPREHENSIVE collection of RELATED data organized for convenient access A database is usually under the control of a DATABASE MANAGEMENT SYSTEM, which is software that, among other things, manages MULTI-USER ACCESS to the database. (usually, but not necessarily. ) ◦ Wk9_Flat_File.accdb Wk9_Flat_File.accdb 7

Database Terms DATABASE MANAGEMENT SYSTEM (DBMS) Provides TOOLS needed to organize data in a flexible manner. It includes:  facilities to add, modify or delete data  Never DELETE, instead flag the data as REDUNDANT.  ask questions (queries) about the data stored  produce reports 8

9 Looks complicated, we’ll go into more detail shortly Entity Relationship Diagram (ERD) Visual display of tables and their relationships for a database Database Terms

Many Types of Databases File Maker Pro Oracle Microsoft ◦ Excel ◦ Access 10

Database Models According to Wikipedia: A database model is the theoretical foundation of a database and fundamentally determines in which manner data can be stored, organized, and manipulated in a database system. It thereby defines the infrastructure offered by a particular database system.database data Simply put, a database model determines HOW data is STORED and ORGANIZED 11

Database Model – Relational Relational database model is the most common Composed of tables, each constructed like a flat file Click here Click here to open an Excel file which illustrates Flat files Keep this file OPEN 12

What are Tables or Entities? TABLES (aka “ENTITIES”) in the relational model are used to represent "things" in the real world. ENTITIES are made up of ROWS and Columns.  Columns are called fields or attributes.  ROWS are called RECORD Within a table, each ROWS is called a RECORD and it represents 1 particular instance of its entity, not unlike the flat file. 13

POLL ON THE GO CLICK HERE CLICK HERE TO GO TO “POLLONTHE GO: OPEN POLL 14

15 Movies mIDMovie 1Toy Story 2Brave Heart 3Dark Skies 4A Beautiful Mind 5Forrest Gump Movie Rentals rIDcIDmID Customers cIDFirstName 1John 2Mary 3Linda 4Shaun 5James Puzzle-USE THIS TO ANSWER NEXT 5 SLIDES

How many customers are there?

How many times have movies been rented?

How many times has customer #3 (Linda) rented a movie?

How many times has movie #5 (Forrest Gump) been rented?

Who was the first customer to rent the movie “A Beautiful Mind”? Mary Linda Shaun 20

What is a Primary Key? A FIELD in the database that guarantees UNIQUENESS SPEEDS data RETRIEVAL Each RECORD in a table must have a PRIMARY KEY Each PRIMARY KEY is the 1 ST attribute (column) listed Click here to take a look again at the Excel file but this time the: RELATIONAL Tab Click here 21

What are Foreign Keys? A FOREIGN KEY is used to indicate a relationship between 2 or more TABLES  Each FOREIGN KEY is a PRIMARY key in another table 22

CREATE RELATIONSHIPS IN MS ACCESS 23

Create Relationships DATABASE TOOLS ribbon > RELATIONSHIPS grouping 24

“Enforce Referential Integrity” A system of rules that MS Access uses to ensure that relationship data is valid and that you CANNOT ACCIDENTALLY DELETE a record in 1 table if a matching record is present in a related table. You can NOT set “Referential Integrity” unless the MATCHING field from the PRIMARY table is a primary key The related fields must have the same Data TYPE 25

26 DATABASE TOOLS tab DESIGN tab TOOLS group RELATIONSHIP REPORT button SAVE CLOSE Relationships “Report”

myitlab 27

ASSIGNMENTS-BE CAREFUL WHEN DOWNLOADING “CHEATING” possibilities BE CAREFUL when you are DOWNLOADING your assignment files. When you DOWNLOAD them, the files come with an embedded ENCRYPTION code IF you COPY THE FILE from another student, your assignment will be flagged with a “POTENTIAL INTEGRITY VIOLATION”,(cheating). EVEN IF YOU SEND AN UN edited file, you may be legitimately doing your own work, but, the file has the ENCRYPTION code your assignment will be flagged with a “POTENTIAL INTEGRITY VIOLATION”, (cheating). 28

ASSIGNMENTS—READ INSTRUCTIONS VERY, VERY CAREFULLY!! You have to be very, very careful with ALL the components in myitlab. The software is extremely specific—it IS case- sensitive, and if you add a space where there shouldn’t be (or vice versa), or forget to include a punctuation mark (or vice versa), myitlab will mark it wrong. When you do your assignments, you must read the instructions extremely carefully, not “skimming over” any of the instructions, just in case you miss a tiny requirement. 29

PRINT OUT ASSIGNMENT MARKS Please make sure that as soon as you get your MARK for ANY assignment, that you do the following: DO NOT CLOSE the dialog box with your mark on it--before doing the following: 1. Hit your PRINT SCREEN button on your keyboard 2. Open MS WORD 3. PASTE 4. Enlarge the “screen capture”, so that it’s readable 5. PRINT out your MARK, AND SAVE the file to the DESKTOP -then UPLOAD the file to SkyDrive 6. You may now close the dialog box. There have been some students who have gotten their mark, but when they close the dialog box with the mark on it-- they receive a “0” in their GRADEBOOK. (This is the mark that I see). This “print out” will be your backup copy—put it in a safe place, until the end of the semester. 30

31 SUBMITTING ASSIGNMENTS: 3 STEPS 1.Click on: 2.Navigate to where your completed assignment file is, double-click on the file, and then click on:

32 AFTER submitting assignment, there is a “TIME LAPSE” You can view results by going to VIEW SUBMISSIONS 3.IMPORTANT: THEN CLICK ON:

33 1.SUBMITTED FILE Opens a.zip file which is a COPY of the file you submitted for your assignment Will give 3 files: 1.SUBMITTED FILE 2.SUMMARY REPORT 3.MARKED UP REPORT

34 click on the arrow to EXPAND the information, to find out exactly where you went wrong. SUMMARY REPORT:

35 1.MARKED UP REPORT:  Click on the check-mark or x- icons to view the detailed results and score of the corresponding instruction step.  If the project required you to insert images or art, those items are hyperlinked and can be selected for more details.  Missing items are highlighted in tan color.  Hidden elements are highlighted in pale yellow color.  Elements that were to be deleted are highlighted in orange color.

36 When doing an exam you must click on the: button to exit. Can do a task 5 times, then it’s wrong myitlab tracks how many attempts you have left Can navigate to another question by hitting If a question does not appear to be working OR if you get to a question & you do not have 5 attempts: Hit your button at the bottom-right of the window myitlab

37 You can skip and go back to questions by clicking on: and myitlab Logistics cont.

38 If you are doing your Training, you do not have to complete it in 1 setting but can click on: And then resume your Training session at a later date will show you step-by-step how to perform the skill will also show you step-by-step BUT: you will need to perform each action along with the prompts You can increase or decrease your font size of your instructions by clicking on these buttons: myitlab TRAINING

HYBRID/HOMEWORK View “14 Week Schedule” > Week 09 > 3 rd Column 39