Data Modeling Essentials 2005 phần 1 ppsx
Data Modeling Essentials 2005 phần 1 ppsx
... a Good Data Model? 10 1. 6 .1 Completeness 10 1. 6.2 NonRedundancy 11 1. 6.3 Enforcement of Business Rules 11 1. 6.4 Data Reusability 11 1. 6.5 Stability and Flexibility 12 1. 6.6 Elegance 13 1. 6.7 Communication ... Normalization in Perspective 415 13 .8 Summary 416 Chapter 14 Modeling Business Rules 417 14 .1 Introduction 417 14 .2 Types of Business Rules 418 14...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 3 ppsx
... UML. Person WomanMan Marriage 1 1 be the husband in 0 * 1 1 be the wife in 0 * be the father of 0 * 1 1 0 * be the mother of 1 1 Simsion-Witt_04 10 /8/04 7:40 PM Page 11 8 facilitate communication, ... of,” particularly in the first model, where they are self-referencing. (Recall our 11 1 Simsion-Witt_04 10 /8/04 7:40 PM Page 11 1 In one organization, senior management wanted...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 4 ppsx
... currency unit. 15 6 ■ Chapter 5 Attributes and Columns 5 Date, C.J. Relational Database Writings 19 89 -19 91, Pearson Education POD, 19 92, Ch. 12 . Simsion-Witt_05 10 /8/04 7:56 PM Page 15 6 key also ... Identity Simsion-Witt_06 10 /11 /04 8:57 PM Page 18 4 datatype requires the number of digits after the decimal point to be spec- ified. If the decimal datatype is not available, the...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 9 ppsx
... Reason 18 12 / 21/ 93 Maintenance 1 12/25/93 Christmas 63 12 /23/93 Local Holiday 2 12 /25/93 Christmas 3 12 /25/93 Christmas 4 12 /25/93 Christmas 5 12 /25/93 Christmas 6 12 /25/93 Christmas Figure 14 .11 ... No Date 18 12 / 21/ 93 Maintenance 1 12/25/93 63 12 /23/93 Local Holiday 2 12 /25/93 3 12 /25/93 National Closure 4 12 /25/93 Date Reason 5 12 /25/93 12 /25/93 Chri...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 2 potx
... HO Employee Number Qualification Description Qualification Year 012 67 Bachelor of Arts 19 70 012 67 Master of Arts 19 73 012 67 Doctor of Philosophy 19 76 70964 Bachelor of Arts 19 69 22 617 Bachelor of Arts 19 72 22 617 Master of Arts 19 77 Employee Table ... department data. Employee Number Qualification Description Qualification Year 012 67 Bachelor of Arts 19 70 012 67 Mast...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 5 pot
... Here is a minimum list. 8.2 .1 Recognition of Data Modeling Let us repeat what we said in Chapter 1: No database was ever built with- out a data model. Unfortunately, many databases have been built ... Bulwer-Lytton 8 .1 Data Modeling in the Real World In the preceding chapters, we have focused largely on learning the lan- guage of data modeling without giving much attention...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 6 pdf
... as those we use for selecting good 276 ■ Chapter 10 Conceptual Data Modeling Simsion-Witt _10 10 /11 /04 8:49 PM Page 276 Chapter 10 Conceptual Data Modeling “Our job is to give the client not what ... Relationships ■ 295 Figure 10 .17 Deliberate creation of asymmetry. Person associated with (lower ID) associated with (higher ID) Simsion-Witt _10 10 /11 /04 8:49 PM Page 295 300...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 7 potx
... will need to 346 ■ Chapter 11 Logical Database Design Part Type Bin be stored in store Figure 11 .13 A one-to-one relationship. Simsion-Witt _11 10 /11 /04 8: 51 PM Page 346 11 .4.5 Complex Attributes In ... combina- tion of < ;Data Item 1 Name>, < ;Data Item 2 Name>, . . . and < ;Data Item n Name>.” 10 .18 The Assertions Approach ■ 317 Simsion-Witt _10 10 /11 /04...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 8 pps
... are in 1NF, 13 .6 Other Normalization Issues ■ 411 Simsion-Witt _13 10 /11 /04 9:54 PM Page 411 will find that a normalization rule is violated or a basic business requirement not supported. 13 .3.3 ... several 392 ■ Chapter 13 Advanced Normalization 1 Date C.J., Darwen H., Lorentzos N, Temporal Data and the Relational Model. Morgan Kaufmann, 2002. Simsion-Witt _13 10 /11 /04 9:54...
Ngày tải lên: 08/08/2014, 18:22
Data Modeling Essentials 2005 phần 10 ppt
... important source of requirements, and for 514 ■ Chapter 17 Enterprise Data Models and Data Management Simsion-Witt _17 10 /8/04 8:08 PM Page 514 16 .6.2 .1 One Fact Table per Star While there is usually ... professionals. Simsion-Witt _17 10 /8/04 8:08 PM Page 502 This page intentionally left blank 16 .6 Modeling for the Data Mart 16 .6 .1 The Basic Challenge In organizing...
Ngày tải lên: 08/08/2014, 18:22