La persona en el contexto formativo

Look in the Control Panel, select administrative tools (shown in figure 11.6, from Windows XP):

Figure 11.6 Administrative Tools

Source: Microsoft Windows XP Control Panel

Open up the Data Sources ODBC icon. This is called the ODBC Data Source Administrato.

Click on the ODBC Drivers tab to see which drivers are installed:

Basic Concepts in DBMS

Figure 11.7 ODBC Data Source Administrator Source: Microsoft Windows XP Control Panel

In the above example (see figure 11.7), we have ODBC drivers for:

Microsoft Access, MS Excel, MS Foxpro, MS Visual FoxPro Borland dBase and Paradox

Text files Oracle 8

MS SQL Server

To add more drivers, download or install the ODBC driver from the database manufacturer. The ODBC driver will then appear on this list.

Clicking on the User DSN tab shows those data sources that have been defined for a user (see figure 11.8).

A user data source simply gives a name to a configuration that includes:

The specific ODBC driver to be used. In some cases, the specific database table or file that will be used. If necessary, a username and password required to gain access to the database. Finally, any other options the particular ODBC driver requires

Figure 11.8 User DSN

Source: Microsoft Windows XP Control Panel User DSNs may only be used by the current user

Systems DSNs may be used by anyone with an account on the computer system Both User and System DSNs are maintianed in the registry of the local machine.

File DSNs store all of the DSN information in a file that can be shared between users of many machines. e.g., put the File DSN on a file server.

Figure 11.9 shows the setup dialog for a Microsoft Access ODBC driver:

Basic Concepts in DBMS

Figure 11.9 Setup dialog for Microsoft Access ODBC Driver Source: Microsoft Windows XP Control Panel

Activity B

1. Explain the following terms:

a. ODBC

b. ODBC Client c. ODBC Driver d. DBMS Server

2. Explain how to setup an ODBC for SQL Server 4.0 Conclusion

Database architectures can be distinguished by examining the way application logic is distributed throughout the system. Application logic consists of three components:

Presentation Logic, Processing Logic, and Storage Logic.

By determining which tier(s) these components are processed on we can get a good idea of what type of architecture and subtype we are dealing with.

5.0 Summary

In this unit, we have learnt:

lxxv. In stand-alone or one-tier database architecture, program (e.g. Microsoft Access) runs on the user's local machine, and references a file that is stored on that

machine's hard drive, thus using a single physical resource to access and process information.

lxxvi. Mainframe Architecture is another form of one-tier database architecture. In this system, large machines provide directly connected unintelligent terminals with the means necessary to access, view and manipulate data.

lxxvii. Common implementation two-tier database architecture is that of a Microsoft Windows based client program that accesses a server database such as Oracle or SQL Server.

lxxviii. Two configurations exist in two-tier architectures namely: A thin-client (fat- server) configuration and fat-client (thin-server).

lxxix. In the n-tier configuration, the client/server model expands to include a middle tier (business tier), which is an application server that houses the business logic.

lxxx. A variation of the n-tier architecture is the web-based n-tier application lxxxi. The middle tier in three-tier architecture contains the business logic.

lxxxii. Open Database Connectivity (ODBC) is Microsoft's strategic interface for accessing data in a heterogeneous environment of relational and non- relational database management systems

lxxxiii. With ODBC, application developers can allow an application to concurrently access, view, and modify data from multiple, diverse databases.

lxxxiv. To use ODBC, client, driver and server components are required 6.0 Tutor Marked Assignment

1a. what do you understand by the term database architectures?

1b. Explain the following database terms i. Application Logic

ii. One-tier Database Architecture iii. Two-tier Database Architecture iv. Three-tier Database Architecture 7.0 Further Reading and other Resources

David M. Kroenke, David J. Auer (2008). Database Concepts. New Jersey . Prentice Hall

Elmasri Navathe (2003). Fundamentals of Database Systems. England. Addison Wesley.

Fred R. McFadden, Jeffrey A. Hoffer (1994). Modern Database management. England.

Addison Wesley Longman

Pratt Adamski, Philip J. Pratt (2007). Concepts of Database Management. United States. Course Technology.

Basic Concepts in DBMS Module 3: Design and Development of Database Applications

Unit 1: Introduction to Microsoft Access Tables

Page

1.0 Introduction 177

2.0 Objectives 177

3.0 Database Design Steps 177

3.1 Planning a Microsoft Access Application 177

3.2 Creating a Microsoft Access Application 177

3.3 Introduction to Microsoft Access 180

3.3.1 Starting Microsoft Access 180

3.3.2 Create a database using the Database Wizard 181 3.3.3 Create a database without using the Database Wizard 181

3.4 Creating Tables in Microsoft Access 183

3.4.1 Creating a Table Using the Design View 183

3.4.2 Primary Key 183

3.4.3 Switching Views 184

3.4.4 Entering Data 184

3.4.5 Manipulating Data 185

3.5 Creating Relationships between Tables 186

4.0 Conclusion 189

5.0 Summary 189

6.0 Tutor Marked Assignment 190

7.0 Further Reading and other Resources 191

1.0 Introduction

This unit introduces fundamental relational database management system (RDBMS) concepts using Microsoft Access, providing a foundation for creating simple tables.

2.0 Objectives

On successful completion you will be able to apply these new skills:

c. Create tables and setting properties and constraints.

d. Create table relationships (One-to-One, One-to-Many, Man-to-Many).