About the extended attribute system tables and DataWindow objects
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, |
|
Columns |
Text specified for labels and headings |
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”