1. University of Sunderland COMM2 Unit 4 Health Information Management Application Building Keys, Data Organisation and Relationships COMM2Q

2. University of Sunderland COMM2 Unit 4 Learning Objectives By the end of the lesson the student will be able to: −Understand use of keys in relational database systems −Understand the importance of data organisation and validation −Understand the types of relationships between tables in a relational database

3. University of Sunderland COMM2 Unit 4 Keys Every record must be uniquely identifiable

4. University of Sunderland COMM2 Unit 4 Key example Customer Family NameJones,Ann,1 Hastings Way Given NameSmith,John,3 Davis Road AddressSmith,Peter,53 Front Street Purchase OrderPurchase Order Order number10021,1/5/10 Date10022,1/5/10 10023,2/5/10

5. University of Sunderland COMM2 Unit 4 Key example Purchase Order LinePurchase Order Line Line number1,6 Number of items2,3 3,1 1,2 1,5Stock Itemapple,0.25 Cost of itemorange,0.30 pineapple,1.23 banana,0.12

6. University of Sunderland COMM2 Unit 4 Data Types Choice of Data Type Formatting Data Data Design vs Data Entry

7. University of Sunderland COMM2 Unit 4 Data Type example Data TypeFormatSize Customer Family NameText>20 Given NameText>20 AddressText>50 Purchase Order Order numberNumberIntegerN/A DateDateShort dateN/A

8. University of Sunderland COMM2 Unit 4 Data Type example Data TypeFormatSize Purchase Order Line Line numberNumberIntegerN/A Number of itemsNumberIntegerN/A Stock ItemTextNone20 Cost of itemCurrencyAutoN/A

9. University of Sunderland COMM2 Unit 4 Validation To ensure that data is only entered in a specific format Validation Rules Validation Text

10. University of Sunderland COMM2 Unit 4 Validation example Validation ruleValidation text <> 0Entry must be a non-zero value. > 1000 Or Is Null Entry must be blank or greater than 1000. Like "A????"Entry must be 5 characters and begin with the letter "A". >= #1/1/10# And <#1/1/11#Entry must be a date in 2010

11. University of Sunderland COMM2 Unit 4 Data Organisation Sorts Indexes

12. University of Sunderland COMM2 Unit 4Relationships 1:1 – one to one 1:N – one to many N:M – many to many

13. University of Sunderland COMM2 Unit 4 Relationships Referential Integrity Foreign keys

14. University of Sunderland COMM2 Unit 4 Relationships example Customer Family NameJones,Ann,1 Hastings Way Given NameSmith,John,3 Davis Road AddressSmith,Peter,53 Front Street Purchase OrderPurchase Order Order number10021,1/5/10,Smith,John Date10022,1/5/10,Jones,Ann *Family Name10023,2/5/10,Jones,Ann *Given Name

15. University of Sunderland COMM2 Unit 4 Relationships example Purchase Order LinePurchase Order Line Line number1,10021,6,001 Order number2,10021,3,002 Number of items 3,10021,1,003 *Item code 1,10022,2,001 1,10023,5,004Stock Item code001,apple,0.25 Item002,orange,0.30 Cost of item 003,pineapple,1.23 004,banana,0.12

16. University of Sunderland COMM2 Unit 4 Learning Objectives −Understand use of keys in relational database systems −Understand the importance of data organisation and validation −Understand the types of relationships between tables in a relational database