Microsoft Access 2010 Bible

Chapter 3: Designing Bulletproof Databases ................................................................................. 93 ...

Part I: Access Building Blocks 94 which means that records are sometimes “lost” and never appear on forms and reports, even thou ...

Chapter 3: Designing Bulletproof Databases 95 Although this data set is very simple, it’s typical of the type of data you might ...

Part I: Access Building Blocks 96 the repeating groups for quantity and title continue to violate the first rule of normalizatio ...

Chapter 3: Designing Bulletproof Databases 97 FIGURE 3.4 First normal form at last! The table in Figure 3.4 contain the same dat ...

Part I: Access Building Blocks 98 This rule means that a table should contain data that represents a single entity. tblBookOrder ...

Chapter 3: Designing Bulletproof Databases 99 FIGURE 3.5 Second normal form: The OrderID field connects these tables together in ...

Part I: Access Building Blocks 100 Notice also that the number of records in tblBookOrders4 has been reduced. This is one of sev ...

Chapter 3: Designing Bulletproof Databases 101 FIGURE 3.6 The numeric CustomerID field results in faster retrievals from tblCust ...

Part I: Access Building Blocks 102 customer’s record in tblBookstores, and use it as the default value for the Discount column b ...

Chapter 3: Designing Bulletproof Databases 103 Similarly, some calculated values may take a long time to evaluate. You may find ...

Part I: Access Building Blocks 104 Finally, always document whatever you’ve done to denormalize the design. It’s entirely possib ...

Chapter 3: Designing Bulletproof Databases 105 The problems with flat-file databases should be immediately apparent from viewing ...

Part I: Access Building Blocks 106 Although you can’t see the relationship in Figure 3.8, Access knows it’s there because a form ...

Chapter 3: Designing Bulletproof Databases 107 always be only one customer related to every sales record. That is, many sales ca ...

Part I: Access Building Blocks 108 entity. Because a person has one and only one birth date, the birth date should be included i ...

Chapter 3: Designing Bulletproof Databases 109 Without a doubt, one-to-many relationships are the most common type encountered i ...

Part I: Access Building Blocks 110 Note Although parent-child is the most common expression used to explain the relationship bet ...

Chapter 3: Designing Bulletproof Databases 111 As indicated in Figure 3.12, many-to-many relationships are somewhat more difficu ...

Part I: Access Building Blocks 112 Integrity Rules Access permits you to apply referential integrity rules that protect data fro ...