Generating and saving a DataWindow object
When you have finished interacting with the wizard, PowerBuilder generates the DataWindow object and
opens the DataWindow painter.
When generating the DataWindow object, PowerBuilder may use information from
a set of tables called the extended attribute system tables. If
this information is available, PowerBuilder uses it.
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, 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 15, “Managing the Database,” and Appendix A, “The Extended
Attribute System Tables”
Saving the DataWindow object
When you have created a DataWindow object, you should save it. The
first time you save it you give it a name. As you work, you should
save your DataWindow object frequently so that you do not lose changes.
To save the DataWindow object:
-
Select File>Save from the menu
bar.If you have previously saved the DataWindow object, PowerBuilder saves the
new version in the same library and returns you to the DataWindow painter.If you have not previously saved the DataWindow object, PowerBuilder displays
the Save DataWindow dialog box. -
(Optional) Enter comments in the Comments box
to describe the DataWindow object. -
Enter a name for the DataWindow object in the DataWindows
box. -
Specify the library in which the DataWindow object is
to be saved and click OK
Naming the DataWindow object
The DataWindow object name can be any valid PowerBuilder identifier
up to 40 contiguous characters. A common
convention is to prefix the name of the DataWindow object with d_.
For information about PowerBuilder identifiers,
see the PowerScript Reference
.
Modifying an existing DataWindow object
To modify an existing DataWindow object:
-
Select File>Open from the menu
bar.The Open dialog displays.
-
Select the object type and the library.
PowerBuilder lists the DataWindow objects in the current library.
-
Select the object you want.
PowerBuilder opens the DataWindow painter and displays the DataWindow object.You
can also open a DataWindow object by double-clicking it in the System
Tree, or, if it has been placed in a DataWindow control window or
visual user object, selecting Modify DataWindow from the control’s
pop-up menu.To learn how you can modify an existing DataWindow object,
see Chapter 18, “Enhancing DataWindow Objects “.