DeletedCount
method (DataWindows)
Description
Reports the number of rows that have been marked for deletion in the
database.
Applies to
|
DataWindow type |
Method applies to |
|---|---|
|
PowerBuilder |
DataWindow control, DataWindowChild object, DataStore |
Syntax
PowerBuilder
|
1 |
long dwcontrol.DeletedCount ( ) |
|
Argument |
Description |
|---|---|
|
dwcontrol |
A reference to a DataWindow control, DataStore, or |
Return value
Returns the number of rows that have been deleted from dwcontrol but
not updated in the associated database table.
Returns 0 if no rows have been deleted or if all the deleted rows
have been updated in the database table. DeletedCount returns -1 if it
fails.
If any argument’s value is null, in PowerBuilder and JavaScript the
method returns null.
Usage
An updatable DataWindow control or DataStore has several buffers.
The primary buffer stores the rows currently being displayed. The delete
buffer stores rows that the application has marked for deletion by calling
the DeleteRow method. These rows are saved until the database is updated.
You can use DeletedCount to find out if there are any rows in the delete
buffer.
If a DataWindow is not updatable, rows that are deleted are
discarded — they are not stored in the delete buffer. Therefore,
DeletedCount returns 0 for a nonupdatable DataWindow unless a method, such
as RowsCopy or RowsMove, has been used to populate the delete
buffer.
Examples
Assuming two rows in dw_employee have been deleted but have not been
updated in the associated database table, these statements set ll_Del to
2:
|
1 2 |
Long ll_Del ll_Del = dw_employee.DeletedCount( ) |
This example tests whether there are rows in the delete buffer, and
if so, updates the database table associated with dw_employee:
|
1 2 3 |
Long ll_Del ll_Del = dw_employee.DeletedCount() IF ll_Del <> 0 THEN dw_employee.Update() |
See also