Introduction to PowerBuilder

What's a DataWindow?

A DataWindow is a data aware object, used to retrieve the data from a database and present it to the user in a wide variety of styles. It also allows the user to change the data and update the database with the changes with some restrictions. DataWindow reduces the need for the code to a minimum by internally issuing appropriate database specific API calls or ODBC calls.

There are two parts in a DataWindow.

• A DataWindow object that has all the definitions
• A DataWindow control with the required script to manipulate the DataWindow object or a DataStore

The later part is explained in the Window painter session, and will be explored in detail in future sessions. This session explains about the DataWindow object. A DataWindow object definition consists of:

• Data source definition such as SELECT statement or name of the stored procedure to execute and its arguments or the result-set definition, etc.
• Presentation definition such as heading/label for each field in the result set, fonts & colors.
• Initial or default values
• Validation rules if the user wants to change the data
• Data source update definition