Net.Data Administration and Programming Guide for OS/400

Why Use Net.Data?

Net.Data is a good choice for creating dynamic Web pages because using the macro language is simpler than writing your own Web server applications and because Net.Data lets you use languages that you already know, such as HTML, SQL, REXX, and JavaScript. Net.Data also provides language environments that access DB2 databases, or use REXX, Perl, and other languages for your applications. In addition, changes to a macro file can be seen instantaneously on a browser.

Net.Data enhances the already extensive data management capabilities of OS/400 with additional capabilities to support emerging and future forms of Internet information processing and presentation. As benefits to your applications, Net.Data:

• Provides separation of data generation and presentation. Net.Data does not impose any restrictions on how the data is presented (for example, with HTML or Javascript). This allows users to easily change the presentation of data using the latest presentation trends.

• Allows you to use existing skills and business logic to generate data by providing the ability to interface with programs written in C, C++, RPG, COBOL, REXX, Java or other languages.

• Provides the ability to develop Internet applications without the need for specialized programming skills.

• Provides high-performance access to data that is stored in DB2 and in any remote DRDA-enabled database.

• Provides a simple, yet powerful macro language that allows for rapid development of Internet and Intranet applications. The Net.Data Web application environment provides the following features:

  Interpreted Macro Language

  The Net.Data macro language is an interpreted language. When Net.Data is invoked to process a macro, Net.Data directly interprets each language statement in a sequential fashion, starting from the top of the file. Using this approach, any changes you make to a macro can be immediately seen when you next specify the URL that executes the macro. No recompilation is required.

  Free Format

  The Net.Data macro language has only a few rules about programming format. This simplicity provides programmers with freedom and flexibility. A single instruction can span many lines, or multiple instructions can be entered on a single line. Instructions can begin in any column. Spaces or entire lines can be skipped. Comments can be used anywhere.

  Variables Without Type

  Net.Data regards all data as character strings. Net.Data uses built-in functions to perform arithmetic operations on a string that represents a valid number, including those in exponential formats. Macro language variables are discussed in detail in Net.Data Macro Variables.

  Built-in Functions

  Net.Data supplies built-in functions that perform various processing, searching, and comparison operations for both text and numbers. Other built-in functions provide formatting capabilities and arithmetic calculations.

  Error Handling

  When Net.Data detects an error, messages with explanations are returned to the client. You can customize the error messages before they are returned to a user at a browser. See Net.Data Reference for more information.