vb.net - Database parent-child connection problmen -

i have following code

 imports system.data    public class reservationlist  private sub guestlisttoolstripmenuitem_click(byval sender system.object, byval e system.eventargs) handles guestlisttoolstripmenuitem.click     'show registration table      guestlistform.show()     me.hide() end sub  private sub highrisetoolstripmenuitem_click(byval sender system.object, byval e system.eventargs) handles highrisetoolstripmenuitem.click     ' shows box     highriseaboutbox.show() end sub  private sub exittoolstripmenuitem_click(byval sender system.object, byval e system.eventargs) handles exittoolstripmenuitem.click     ' terminates program     highriseaboutbox.show()     me.close() end sub  private sub newreservationtoolstripmenuitem_click(byval sender system.object, byval e system.eventargs) handles newreservationtoolstripmenuitem.click     ' restarts program     newreservationform.show()     me.close() end sub  private sub exitbutton_click(byval sender system.object, byval e system.eventargs) handles exitbutton.click     ' terminates program      highriseaboutbox.show()     me.close() end sub  private sub reservationlist_load(byval sender system.object, byval e system.eventargs) handles mybase.load      'todo: line of code loads data 'cottagesdataset.guests' table. can move, or remove it, needed.     me.gueststableadapter.fill(me.cottagesdataset.guests)     'todo: line of code loads data 'cottagesdataset.reservations' table. can move, or remove it, needed.     me.reservationstableadapter.fill(me.cottagesdataset.reservations)  end sub  private sub last_namelabel_click(byval sender system.object, byval e system.eventargs)  end sub   private sub last_namecombobox_selectedindexchanged(byval sender system.object, byval e system.eventargs) handles last_namecombobox.selectedindexchanged  end sub end class 

and when run (debug) program this

i trying setup parent-child relation show shown below:

and .xsd relation have

so that's have can show you. idea why getting error? seems check on database have setup same way. followed book tutorial , didnt miss anything. i'm close dump whole idea make work.

thanks

the 'failed enable constraints' error occurs when have form of database schema error.

to fix them:

1. make sure primary keys disallow null values, , haven't stored nulls in there yet.

2. make sure 'relation' columns (last name, guest) non-null, , haven't stored nulls in there yet.

3. if changed length of strings last name, guest can store, after adding data, might hit issue encountered here: http://social.msdn.microsoft.com/forums/en-us/vsexpressvb/thread/27aec612-5ca4-41ba-80d6-0204893fdcd1/