The extended attribute system tables are a set of tables maintained by the Database painter. They contain information about database tables and columns. Extended attribute information extends database definitions by recording information that is relevant to using database data in screens and reports.
For example, labels and headings you defined for columns in the Database painter are used in the generated DataWindow object. Similarly, if you associated an edit style with a column in the Database painter, that edit style is automatically used for the column in the DataWindow object.
When generating a DataWindow object, PowerBuilder uses the following information from the extended attribute system tables:
For |
PowerBuilder uses |
|---|---|
Tables |
Fonts specified for labels, headings, and data |
Columns |
Text specified for labels and headings Display formats Validation rules Edit styles |
If there is no extended attribute information for the database tables and columns you are using, you can set the text for headings and labels, the fonts, and the display formats in the DataWindow painter. The difference is that you have to do this individually for every DataWindow object that you create using the data.
If you want to change something that came from the extended attribute system tables, you can change it in the DataWindow painter. The changes you make in the DataWindow painter apply only to the DataWindow object you are working on.
The advantage of using the extended attribute system tables is that it saves time and ensures consistency. You only have to specify the information once, in the database. Since PowerBuilder uses the information whenever anyone creates a new DataWindow object with the data, it is more likely that the appearance and labels of data items will be consistent.
For more information about the extended attribute system tables, see Chapter 16, “Managing the Database,” and Appendix A, “The Extended Attribute System Tables.”
