Getting Started With DDF Builder

This section includes the following topics:

What Is DDF Builder?

DDF Builder is a Java-based utility that allows you to create, change, and view Pervasive.SQL database files. The ability to change or create a file depends on the type of file. In broad terms, DDF Builder allows you to perform three types of actions:

Most of the functionality in DDF Builder supports one or more of these three actions.

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Note
DDFs define the schema for your SQL metadata. DDFs are system tables that allow DDF Builder to represent SQL access as objects called "SQL tables." Rather than modifying one or more DDFs directly, you work with the SQL table objects. DDF Builder automatically modifies the DDFs as you create, change, or delete SQL tables.

One set of DDFs applies to the entire database. All SQL tables for the database are defined in the same set of DDFs.

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What Do You Need To Know Before Using DDF Builder?

The two primary methods in which data is accessed from Pervasive.SQL databases are transactional and relational. For much of the functionality in DDF Builder, you need to understand transactional access. Other areas of functionality require that you are familiar with relational database concepts in general. To take advantage of all features of the utility, you need in-depth knowledge of both Pervasive.SQL access methods: transactional and relational.

A single application program may include both types of access. For example, an application may use transactional access for adding and changing data, and relational access for querying the data and report writing.

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Note
This book assumes that you thoroughly understand the transactional access method and relational concepts. No attempt is made to explain them or to define common terms, such as keys, indexes, pages types, schema, and so forth.

Listed below are references to other Pervasive.SQL books if you need to further your understanding before attempting to use DDF Builder. Note that, by default, the Pervasive.SQL Software Development Kit (SDK) books are installed with the Pervasive.SQL database engine. Refer to the Readme file provided with the database engine for how to access the SDK documentation.

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Transactional Access

With transactional access, an application program navigates up and down along either physical or logical pathways through data records. Using a transactional API, an application program provides direct control and allows a developer to optimize data access based on knowledge of the underlying structure of the data. Using the Btrieve API is an example of transactional access.

Refer to the following books to further your understanding of transactional access:

Relational Access

Relational is an access method in which data is represented as collections of tables, rows, and columns. The relational model insulates the developer from the underlying data structure and presents the data in a simple table format. ODBC is an example of a relational access method.

Refer to the following books to further your understanding of relational access:

What Do You Need To Do Before Using DDF Builder?

DDF Builder can alter the structure of your database. As a precaution before using the utility, always back up any Btrieve files with which you intend to work. (Btrieve files are also referred to as "data" files because the data is stored within the page structure of the file.)

Note that DDF Builder does not allow you to modify the record layout structure of existing Btrieve files. You can create new Btrieve files with the utility if you choose.

How Do You Start DDF Builder?

To start DDF Builder on a Windows machine:

How Do You Access the Documentation?

The documentation for DDF Builder includes a Readme file and JavaHelp. You must install DDF Builder before you can access the JavaHelp.

To access DDF Builder Readme file:

The Readme file, readme_ddfbldr.htm, is provided in the download archive file and can be accessed before installing the product.

To access DDF Builder JavaHelp documentation: