Exploring Microsoft Access 2003 Chapter 5 One-to-Many Relationships : Subforms and Multiple Table Queries

Objectives (1 of 2) One-to-many relationship essential in database design Use the Relationship window Define referential integrity Distinguish between a main form and a subform

Objectives (2 of 2) Create a query based on multiple tables Create a main form with two subforms

Overview One-to-many relationships between tables is the real power of Access Primary key of one table is foreign key of the related table Referential integrity ensures consistency between tables Main forms and subforms created from related tables. Reports based on a multiple-table query

Case Study Consumer Loans Understanding the need for a relational database One-to-many relationship – use Relationships window Need a primary key, a unique identifier Foreign key in the many table is the primary key in the one table Enforce referential integrity

Relationships Window ConsultantID is primary key in Consultant table Relationship line ConsultantID is foreign key in Clients table

Referential Integrity Delete Record button Click + to display related records You cannot delete a Consultant without first deleting related Clients

One-to-Many Relationships Hands-On Exercise 1 Open the National Bank Database Create and Delete Relationships Add a Customer Record Add a Loan Record Referential Integrity Close the Database

Subforms Subform is a form within a form Main form would be based on primary table while subform is based on related table Use Subform Wizard Can be created either on main form or dragged from a separate form

Subform Consultant C01 Client related to Consultant C01 Status bar for Clients form Status bar for Consultants form

Creating a Subform Hands-On Exercise 2 Create Customers Form using Form Wizard Modify Customers Form Create Loans Subform View Customers Form Add Payment Amount Enter a New Loan Print the Form

Multiple Table Queries Query information from two tables Create a select query using both tables Query window displays selected fields of each table

Multiple Table Queries Run button Column selector Select table Enter criteria

Queries and Reports Hands-On Exercise 3 Create a Select Query Move and Size the Field Lists Create and Run the Query Create and Print a Report

Expanding the Database Can expand a database without disturbing existing tables Use relationship window to establish how fields from specific tables will be related Can use multiple subforms

Linked Subforms Hands-On Exercise 4 Add a relationship Create the Payments Subform Change the Default View The Loans Subform in Form View The Customers Form The Finishing Touches Make Your Payments

Chapter 5 Summary (1 of 2) Access database may contain multiple tables Each table has a primary key which is the foreign key of a related table Relationships window to create one-to-many relationships Referential integrity ensures consistency between related tables

Chapter 5 Summary (2 of 2) Subform is a form within a form A main form can have multiple subforms Select query can include fields from several tables Tables can be added at any time without disturbing existing data

Practice with Access (1 of 2) 1. Adding Clip Art 2. The Report Wizard 3. Employees by Location 4. Employees by Title

Practice with Access (2 of 2) 5. The Switchboard 6. The Table Analyzer Wizard 7. Synchronizing Reports 8. Data Access Pages

Case Studies Recreational Sports League The Personnel Director The Franchise Widgets of America