BUG: GRID: SET RELATION TO Does Not Break Relation Properly

• Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 5.0, 5.0a

SYMPTOMS

When you use the SET RELATION TO command to break an existing relationship, the only records displayed from the relationship's child table are those that are related to the current parent record and beyond. Any child records that match parent records prior to the current parent record are left out.

WORKAROUND

Method One

After using the SET RELATION TO command to break the relation, use the SELECT command to select the child table, and then use the USE command. This closes the child table.

Open the table again by using the USE command. Set the RecordSource property of the grid back to the child alias. The code to do this would look similar to this code:

   SELECT orders              && Select the child table
   USE                        && Close the child table
   USE orders ORDER cust_id   && Open the child table and reset the order
   ThisForm.Grid1.RecordSource = "Orders"    && Reset RecordSource
   ThisForm.Refresh           && Refresh the form

Method Two

Use the following code to break the relation. This will allow you to see all the child records in the grid without resetting any of the grid properties.

ThisForm.LockScreen = .T. && Lock the form

   SELECT orders              && Select the child table
   nChildRec = RECNO()        && Store the current child record number
   SELECT customer            && Select the parent table
   nParentRec = RECNO()       && Store the current parent record number
   GO TOP                     && Go to the top record in the parent table
   Thisform.Refresh()
   SET RELATION TO            && Break the relation
   ThisForm.Grid1.RecordSource = ThisForm.Grid1.RecordSource
   * Force the grid to look at the child table again
   SELECT orders              && Select the child table
   GO nChildRec               && Go to the child record we were on
   SELECT customer            && Select the parent table
   Go nParentRec              && Go to the parent record we were on
   Thisform.Refresh()
   ThisForm.LockScreen = .F.  && Unlock the form

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Problem

1. Create a new form, and on that form, place a text box, a grid, a vcr command group, and a command button to break the relation. (The vcr command group can be found in the Buttons.vcx file located in VFP\Samples\Classes.)

2. In the Load event of the form, add the following code:

   USE customer IN 0 * Customers.dbf and Orders.dbf can be found in VFP\Samples\Data USE orders IN 0 ORDER cust_id SELECT CUSTOMER SET RELATION TO cust_id INTO orders

3. In the Init event of the form, add the following code:

   ThisForm.Text1.ControlSource = "cust_id" ThisForm.Grid1.RecordSource = "orders" ThisForm.Grid1.RecordSourceType = 1

4. Place the following code in the Click event for the Break command button:

   SELECT customer SET RELATION TO thisform.grid1.recordsource='orders' ThisForm.Refresh

5. In the Unload event of the form add the following code:

   select customer use select orders use

6. Open the View window, and run the form.

7. Make a note of the customer id number in the text box, and skip through the first three records.

8. Click the Break command button.

9. Notice that the relation no longer exists in the View window and the only records available in the grid are those that match the current parent record and beyond. No previous records are available.