Chap 4 relational data model

... Outline  Relational Model Concepts  Relational Model Constraints and Relational Database Schemas  Update Operations and Dealing with Constraint Violations Relational Model Concepts  The relational ... Model of Data is based on the concept of a Relation  A Relation is a mathematical concept based on the ideas of sets  The strength of the relational...

Ngày tải lên: 12/05/2014, 11:55

... 20 10 Chương MÔ HÌNH QUAN HỆ II Chuyển mô hình ER sang mô hình quan hệ Bước Thuộc tính đa trò MAPB TENPB DIADIEM PHONGBAN DIADIEM_PHG (MAPB, DIADIEM) 21 Chương MÔ HÌNH QUAN HỆ II Chuyển mô hình ... = 1,m Chương MÔ HÌNH QUAN HỆ ĐỊNH NGHĨA QUAN HỆ • Lược đồ quan hệ (relation scheme) R(A1, A2, , An): – Trong R tên lược đồ quan hệ – A1, A2, …, An thuộc tính l...

Ngày tải lên: 05/07/2014, 16:20

... actions that define the relationship between each pair of entities, and label the line with the relationship verb This is the initial ER diagram for the logical data model Answer in v04_160 9a_ act42-1.bmp ... v04_160 9a_ act42-1.bmp Activity 4.2: Creating a Logical Data Model Exercise 2: Determining Cardinality and Existence In this exercise, you will use the syntax discu...

Ngày tải lên: 21/12/2013, 06:16

... float datatype can be used The decimal Datatype Number accommodated integer Figure 5 .4 Length (var)char 36 1,296 46 ,656 1,679,616 60 ,46 6,176 2,176,782,336 78,3 64, 1 64, 096 2.82×1012 127 32,767 2, 147 ,48 3, 647 ... (user-defined datatypes), you should assign to each column the appropriate DBMS datatype (as indicated in Sections 5 .4. 4.1 thru 5 .4. 4 .4) If, however, you are using an...

Ngày tải lên: 08/08/2014, 18:22

... 2,380 180,880 176.6 K B Customer 94 3,000 282,000 275 .4 K B Inventory 30 3,068,100 92, 043 ,000 89.9 M B Sale 43 8,112,000 348 ,816,000 340 .6 M B Total 44 1, 349 ,3 64 431 M B This is a very preliminary ... developed data marts Second, analyzing relationships in the source data can identify areas on which to focus your data warehouse development efforts 52 Data Modeling Tech...

Ngày tải lên: 14/08/2014, 06:22

... B +37 -1 4 +109 +79 +16 Nhãn C -3 1 -1 8 +90 +16 -1 41 Nhãn D +97 +39 + 242 +118 +76 Giá +25% -2 52 -3 67 -4 63 -1 40 -8 1 Giá +50% -5 42 -7 83 -6 77 -3 20 -3 52 Đồng hồ lắp sẵn +152 +60 +232 +188 +1 74 An toàn ... cầu khách hàng ngoại Cầu nhu cầu khách hàng sinh nội sinh Quan điểm nhìn nhận thu hẹp Quan điểm nhìn nhận toàn cầu nước khác...

Ngày tải lên: 26/10/2012, 09:12

... of querying EF data: retrieving entity data using Entity SQL and accessing objects directly through the Entity Framework’s Object Services layer Chapter 14  Visualizing Data Models 243 Chapter ... enter SalesOrderEntities as the configuration name Click Next Chapter 14  Visualizing Data Models 229 The Choose Your Database Objects panel appears In this hierarchical list of objec...

Ngày tải lên: 03/10/2013, 00:20

... s DATA MODELS, DATASETS, AND THE ADO.NET INTERFACE structure to the underlying source table from the database A dataset like this is also commonly known as a typed dataset We create a typed dataset ... PM Page 60 CHAPTER s DATA MODELS, DATASETS, AND THE ADO.NET INTERFACE Figure 3-10 Steps to add a data table to dataset Click the header of the newly create...

Ngày tải lên: 05/10/2013, 08:48

... access to stored data It is the biggest element a data model supports The relational database is the standard database supported by the Data Modeling UML profile An object relational database, an ... columns and it can also exist on a single column Summary With the data modeling for UML profile, the UML fully supports data modeling needs It allows the sup...

Ngày tải lên: 10/12/2013, 15:15

... meeting each of these challenges through good database design, you improve the performance of your database Overview of Data Modeling and Database Design 8Ć5 8Ć6 Introduction to Oracle: SQL and PL/SQL ... refine the system Overview of Data Modeling and Database Design 8Ć7 8Ć8 Introduction to Oracle: SQL and PL/SQL Using Procedure Builder Database De...

Ngày tải lên: 10/12/2013, 17:15

... 74 Activity 9.4: Identifying Data Access Requirements Exercise 1: Identifying a Data Access Method for a Scenario (10 minutes) ! Identify data access requirements Participate ... generated and copies to be stored in a repository for easy access in the future Solution A B Activity 9.4: Identifying Data Access Requirements 75 Exercise 2: Analyzing Technolog...

Ngày tải lên: 21/12/2013, 06:16

... S_ORD Table Overview of Data Modeling and Database Design 8Ć27 8Ć28 Introduction to Oracle: SQL and PL/SQL Using Procedure Builder Designing the Database The database design stage produces design ... refine the system Overview of Data Modeling and Database Design 8Ć7 8Ć8 Introduction to Oracle: SQL and PL/SQL Using Procedure Builder Database Design...

Ngày tải lên: 21/12/2013, 06:17

... include: • Scaling the MSF Team Model • Applying the MSF Team Model v vi Module 4: MSF Team Model Background on Scaling the MSF Team Model Scaling for Small Projects Although the Team Model consists ... successful team, and the MSF Team Model Team Goals for Success The MSF Team Model Principles of a Successful Team Scaling the MSF Team Mod...

Ngày tải lên: 24/01/2014, 10:20

... implementations differ, NoSQL database management systems share a common set of characteristics: • No schema required Data can be inserted in a NoSQL database without first defining a rigid database schema ... necessity, forced to invent new approaches to data management These NoSQL or non-relational database technologies are a better match for the needs of modern int...

Ngày tải lên: 19/02/2014, 12:20

... ABSTRACT Health and Wealth of Elderly Couples: Causality Tests Using Dynamic Panel Data Models A positive relationship between socio-economic status (SES) and health, the so-called "health- wealth ... Health and Wealth of Elderly Couples: Causality Tests Using Dynamic Panel Data Models Pierre-Carl Michaud CentER, Tilburg University and...

Ngày tải lên: 05/03/2014, 18:20