RejectChanges on a parent table : Exception

[dubem1]

Hello

 

I am in a situation where I have a Parent-Child relationship between to table. I am using a typed dataset

 

I add a record to the parent table and then a a record to the child table, associated to the parent record a just added.

 

Then I do a rejectChanges on the parent table. I expect that both parent record and child record will be "eliminated" but instead, I have an exception saying

 

"Cannot make this change because constraints are enforced on relation

ParentToChild, and changing this value will strand child rows."

 

What's the problem???

 

 

Thank you