How to: Turn Off Constraints While Filling a Dataset
If a dataset contains constraints (such as a foreign-key constraint) it is possible to cause exceptions to be thrown depending on the order of operations performed against the dataset. For example, loading child records before loading the related parent records can violate the constraint and cause an exception. As soon as you load a child record the constraint checks for the related parent record and raises an error. If there were no mechanism to allow temporary constraint suspension, an error would be raised every time you tried to load a record into the child table. Another way to suspend all constraints in a dataset is with the BeginEdit, and EndEdit properties.
To suspend update constraints programmatically
The following example shows how to temporarily turn off constraint checking in a dataset: