iX V6.5 (30391-90011)

32 Chapter1

Introduction

How to Use TurboIMAGE/XL

The following steps summarize how to use TurboIMAGE/XL. Refer to Figure 1-1. for an

illustration of each of the steps.

1. Design the Database.

A database designer (system analyst) or team of designers determine what data is

required by all the application projects that will share the database. They determine

which data should be protected from unauthorized access and how the data will be

used. These design considerations and others described in appendix C determine the

database content and structure.

2. Describe the Database.

After the design is complete, it is described using the TurboIMAGE/XL Database

Deﬁnition Language (DDL). This external deﬁnition is called a schema. The database

creator processes the schema using the TurboIMAGE/XL Schema Processor which

creates an internal deﬁnition of the database called a root ﬁle. The person who creates

the root ﬁle is identiﬁed as the database creator and can subsequently create and

initialize the database. Chapter 3 contains the description language syntax and

operating instructions for the Schema Processor.

3. Create the Database Files.

DBUTIL, a TurboIMAGE/XL utility program, builds the database ﬁles according to

requirements of the database structure speciﬁed in the root ﬁle. The ﬁles contain no

data initially.

4. Store and Retrieve the Data.

TurboIMAGE/XL provides a set of library procedures that can be called from BBASIC,

C, COBOL II, FORTRAN 77, Pascal, or TRANSACT/V language application programs.

The database can also be used with RPG programs but the Report Program Generator

issues the calls to TurboIMAGE/XL procedures.

The application project members can design and write programs in the programming

language which best suits their needs and call the TurboIMAGE/XL procedures to

store, modify, retrieve, and delete data. These procedures rapidly locate the data,

maintain pointer information, manage the allocated ﬁle space, and return status

information about the activity requested. Each procedure is described in detail in

chapter 5, and examples of calling several procedures from the different languages are

given in chapter 6.

5. Maintain the Database.

The TurboIMAGE/XL utility programs can be used to maintain backup copies of the

database and perform other utility functions such as logging, recovering, or

restructuring the database. These programs are described in chapters 7 and 8. You can

also use the TurboIMAGE/XL procedures to write your own maintenance programs, or

you can acquire a database restructuring facility.