- Data is often a company's most valuable asset and belongs in a data model that avoids anomalies like redundant data. - When building a database, identify required data fields, organize related fields into tables, and define primary keys and relationships between tables to avoid issues from updates, deletions, and insertions. - Normalization is the process of structuring data in tables to eliminate anomalies and ensure tables are in at least third normal form.

1. BSYS 2060 Lecture 2 – Data Literacy & Data Modeling

2. We live in an information age where data is king.

3. Data often most valuable asset of a companye.g. Aeroplan worth more than Air Canada

4. We live in a data mash-up world.

9. Where does data belong?

10. DiasporaMany “fly by night” Web 2.0 appsSelf-hostedWebsite containing all your dataYou don’t control the data at allYou control completelyNot so easy...convenientTrend is towards you controlling your data

15. Who owns data?

17. Building a database for an organization?

18. What is the organization’s mission?

19. What is the project’s mission?

20. What data is required to make good decisions or for other reporting needs?

21. What data is currently being collected?

22. How is the data collected being used?

23. What data should be collected?

24. What are the main data entities?These will become your tables

25. What are the required fields and field data types?

26. What are the relationships between the tables?

27. Select your tools?e.g. MS Access, MS SQL, MySQL, OracleWhat is being used now if anything?

28. Be careful of the hammer!To a hammer, everything looks like a nail. If you only know MS Access, you may see always see MS Access as the solution even when it’s not. If you only know MS Excel, it seems like the perfect choice!Source:http://www.flickr.com/photos/fixersphotos/3199566032/

29. NormalizationA brief introduction to the first three forms...

30. “Normalization”In the field of relational database design, normalization is a systematic way of ensuring that a database structure is suitable for general-purpose querying and free of certain undesirable characteristics—insertion, update, and deletion anomalies—that could lead to a loss of data integrity.Codd, E.F. The Relational Model for Database Management: Version 2. Addison-Wesley (1990), p. 271

32. “...insertion, update, and deletion anomalies...”Until a Course Code is assigned to this record, it can not be inserted in the table

33. “...insertion, update, and deletion anomalies...”An edit made to one record may not be made to ALL records for the same employee

34. “...insertion, update, and deletion anomalies...”If the Course Code is deleted the information for the Faculty Member will be lost.

35. Three Normal Forms1NFEliminate repeating groupsNo redundant data2NFEliminate independent dataAll fields depend on Primary Key3NFEliminate dependency on non-key fieldsFields do not depend on each other

36. Un-Normalized Table (i.e. Excel)

37. First Normal Form (1NF)0NF – “un-normalized”1NF

38. Second Normal Form (2NF)1NF2NF

39. Third Normal Form (3NF)2NF3NF

40. Access Tutorial 2Building a Database and Defining Table Relationships

41. ObjectivesLearn the guidelines for designing databases and setting field propertiesView and modify field data types and formattingCreate a table in Design viewDefine fields and specify a table’s primary keyModify the structure of a tableNew Perspectives on Microsoft Office Access 200741

42. ObjectivesImport data from an Excel worksheetCreate a table by importing an existing table structureDelete, rename, and move fieldsAdd data to a table by importing a text fileDefine a relationship between two tablesNew Perspectives on Microsoft Office Access 200742

43. Guidelines for Designing DatabasesIdentify all the fields needed to produce the required informationOrganize each piece of data into its smallest useful partGroup related fields into tablesDetermine each table’s primary keyInclude a common field in related tablesAvoid data redundancyDetermine the properties of each fieldNew Perspectives on Microsoft Office Access 200743

44. Guidelines for Setting Field PropertiesYou must name each field, table, and other objectChoose an appropriate data typeNew Perspectives on Microsoft Office Access 200744

45. Guidelines for Setting Field PropertiesThe Field Size property defines a field value’s maximum storage size for Text, Number, and AutoNumber fields onlyByteIntegerLong IntegerSingleDoubleReplication IDDecimalNew Perspectives on Microsoft Office Access 200745

46. Viewing and Modifying Field Data Types and FormattingNew Perspectives on Microsoft Office Access 200746

47. Creating a Table in Design ViewNew Perspectives on Microsoft Office Access 200747

48. Defining a Field in Design ViewIn the Field Name box, type the name for the field, and then press the Tab keyAccept the default Text data type, or click the arrow and select a different data type for the field. Press the Tab keyEnter an optional description for the field, if necessaryUse the Field Properties pane to type or select other field properties, as appropriateNew Perspectives on Microsoft Office Access 200748

49. Defining a Field in Design ViewNew Perspectives on Microsoft Office Access 200749

50. Specifying the Primary Key in Design ViewIn the Table window in Design view, click in the row for the field you’ve chosen to be the primary key. If the primary key will consist of two or more fields, click the row selector for the first field, press and hold down the Ctrl key, and then click the row selector for each additional primary key fieldIn the Tools group on the Table Tools Design tab, click the Primary Key buttonNew Perspectives on Microsoft Office Access 200750

51. Specifying the Primary Key in Design ViewNew Perspectives on Microsoft Office Access 200751

52. Moving a FieldTo move a field, you use the mouse to drag it to a new location in the Table window in Design viewNew Perspectives on Microsoft Office Access 200752

53. Adding a Field Between Two Existing FieldsIn the Table window in Design view, select the row for the field above which you want to add a new fieldIn the Tools group on the Table Tools Design tab, click the Insert Rows buttonDefine the new field by entering the field name, data type, optional description, and any property specificationsNew Perspectives on Microsoft Office Access 200753

54. Adding a Field Between Two Existing FieldsNew Perspectives on Microsoft Office Access 200754

55. Importing Data from an Excel WorksheetThe import process allows you to copy the data from a source without having to open the source fileClick External Data on the RibbonClick the Excel button in the Import group to start the wizardNew Perspectives on Microsoft Office Access 200755

56. Importing Data from an Excel WorksheetNew Perspectives on Microsoft Office Access 200756

57. Importing Data from an Excel WorksheetNew Perspectives on Microsoft Office Access 200757

58. Importing Data from an Excel WorksheetNew Perspectives on Microsoft Office Access 200758

59. Creating a Table by Importingan Existing Table StructureMake sure the External Data tab is the active tab on the RibbonIn the Import group, click the Access buttonClick the Browse buttonNavigate to the fileMake sure the Import tables, queries, forms, reports, macros, and modules into the current database option button is selected, and then click the OK buttonClick the Options buttonNew Perspectives on Microsoft Office Access 200759

60. Creating a Table by Importingan Existing Table StructureNew Perspectives on Microsoft Office Access 200760

61. Deleting a Field from a Table StructureIn Datasheet view, select the column heading for the field you want to deleteIn the Fields & Columns group on the Datasheet tab, click the Delete buttonorIn Design view, click in the Field Name box for the field you want to deleteIn the Tools group on the Table Tools Design tab, click the Delete Rows buttonNew Perspectives on Microsoft Office Access 200761

62. Deleting a Field from a Table StructureNew Perspectives on Microsoft Office Access 200762

63. Adding Data to a Table by Importing a Text FileClick the External Data tab on the RibbonIn the Import group, click the Text File buttonClick the Browse buttonNavigate to the fileClick the Append a copy of the records to the table option buttonSelect the tableClick the OK buttonNew Perspectives on Microsoft Office Access 200763

64. Adding Data to a Table by Importing a Text FileNew Perspectives on Microsoft Office Access 200764

65. Defining Table RelationshipsOne of the most powerful features of a relational database management system is its ability to define relationships between tablesYou use a common field to relate one table to anotherNew Perspectives on Microsoft Office Access 200765

66. Defining Table RelationshipsNew Perspectives on Microsoft Office Access 200766

67. Defining Table RelationshipsA one-to-many relationship exists between two tables when one record in the first table matches zero, one, or many records in the second table, and when one record in the second table matches at most one record in the first tableThe Primary table is the “one” in a one-to-many relationshipThe Related table is the “many” table New Perspectives on Microsoft Office Access 200767

68. Defining Table RelationshipsReferential integrity is a set of rules that Access enforces to maintain consistency between related tables when you update data in a databaseThe Relationships window illustrates the relationships among a database’s tablesClick the Database Tools tab on the RibbonIn the Show/Hide group on the Database Tools tab, click the Relationships buttonNew Perspectives on Microsoft Office Access 200768

69. Defining Table RelationshipsNew Perspectives on Microsoft Office Access 200769

70. Defining Table RelationshipsNew Perspectives on Microsoft Office Access 200770

71. Defining Table RelationshipsNew Perspectives on Microsoft Office Access 200771