XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 1 Preparing To Automate Data Management Chapter 1 “You can use all the quantitative data you can get, but you still have to distrust it and use your own intelligence and judgment.” — Alvin Toffler

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 2 Chapter Introduction Discovery phase includes  Gathering all existing data  Researching missing and incomplete data  Talking with users about data output needs Subsequent steps in process include  Putting data into groups called tables  Identifying unique values for each record in those tables  Designing database to produce desired output

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 3 Database Design Process: The Discovery Phase

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 4 Level 1 Objectives: Examining Existing and Missing Sources of Data Discover and evaluate sources of existing business data Research sources of missing or incomplete data Assign data to tables and use field types and sizes to define data

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 5 Discovering and Evaluating Sources of Existing Data Identify information that organization needs to manage and organize Might begin to see patterns that indicate how to organize data Database management system (DBMS)  Includes: Oracle ColdFusion Microsoft Access MySQL

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 6 Discovering and Evaluating Sources of Existing Data (continued) Data duplication  Undesirable Additional space required in database to store extra records Leads to inconsistent and inaccurate data Data redundancy  Same data repeated for different records

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 7 Researching Sources of Missing Data Part of discovery phase Must ask right questions of right people to get right answers

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 8 Assimilating the Available Information and Planning the Database First step in database design  Determine best way to organize data into logical groups of fields Field  Single characteristic of entity  Also called column Record  Values in each field in table  Also called row

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 9 Assimilating the Available Information and Planning the Database (continued) Table  Collection of fields that describe one entity  Also called entity or relation Database  Collection of one or more tables Relational database  Contains related tables through fields that contain identical data

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 10 Evaluating Field Values and Assigning Appropriate Data Types Data type  Determines how to store data in field DBMSs use different names for some data types How do you determine which data type to assign each field?  Depends on what function you want to derive from data  Each data type has different properties

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 11 Common Data Types and Their Descriptions

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 12 The Text and Memo Data Types Text data type  Letters and numbers  Not used in calculations or formulas  Stores maximum of 255 characters  Default for all fields created in access database Memo data type  Store long passages of text  Stores maximum of 65,535 characters

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 13 The Number Data Type Stores both positive and negative numbers Contains up to 15 digits Use for values used in calculations

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 14 The Currency Data Type Includes two decimal places and displays values with dollar sign Use for monetary values

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 15 The Date/Time Data Type Display values in format mm/dd/yyyy  Can also include time in different formats Used in calculations if necessary

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 16 The AutoNumber Data Type Unique to Access Number automatically generated by access Produces unique values for each record Useful to distinguish two records that share identical information Produces values of up to nine digits

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 17 The Yes/No Data Type Assigned to fields requiring  Yes/no  True/false  On/off Takes up one character of storage space Make data entry easy  Check box

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 18 The OLE Object Data Type Used to identify files created in another program  Then linked or embedded in database Abbreviation for object linking and embedding

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 19 The Hyperlink Data Type Assigned to fields that contain hyperlinks to  Web pages  addresses  Files that open in Web browser client Another application

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 20 The Lookup Wizard Data Type Creates fields to look up data in  Another table  Or list of values created for field Makes data entry easy Ensures that valid data entered into field

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 21 Selecting the Correct Data Type Helps store correct data in correct format while using least amount of space Eases data entry and interactivity with data Choosing certain data types results in user-friendly interactive features  Drop-down menus  Check boxes  Hyperlinks Correctly manipulate data

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 22 Assigning the Correct Field Size for Text Fields Important to consider field size when assigning data types  Minimize space reserved for each record by assigning smallest data type that will store data Be conservative when assigning field sizes  But not too conservative

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 23 Assigning the Correct Field Size for Number Fields

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 24 Dividing the Existing and Missing Data into Tables Tables  Single most important component of database  Most databases contain Multiple tables Hundreds or even thousands of records Primary key  One field that creates unique value in each record  Used to identify each record in table  May be a combination of fields

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 25 Database Design Process: Planning the Tables

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 26 Naming Conventions Database tables must  Have unique names  Follow established naming conventions General rules for naming objects  Object names cannot exceed 64 characters  Object names cannot include period, exclamation point, accent grave, or brackets  Object names should not include spaces  Most developers capitalize first letter of each word when table name includes two words

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 27 Leszynski/Reddick Naming Conventions for Database Objects

XP Chapter 1 Succeeding in Business with Microsoft Office Access 2003: A Problem-Solving Approach 28 Level 1 Summary Discovery phase Identify existing and missing data Determine tables  Determine data types Follow naming conventions