Foreign key without constraints?

Question

I was studying DataRelations in Ado.Net and came across this constructor

public DataRelation(
    string relationName,
    DataColumn parentColumn,
    DataColumn childColumn,
    bool createConstraints
)

Here, the last parameter is createConstraints , which is explained by MSDN as

createConstraints

Type: System.Boolean

A value that indicates whether constraints are created. true, if constraints are created. Otherwise, false.

If I set it to false then what happens? How does it create a foreign key without constraints?

Answer 1

Yes, the relationship will be created without a constraint being added to ConstraintCollection

More on constraints:

Relationships can also cascade various changes from the parent DataRow to its child rows. To control how values are changed in child rows, add a ForeignKeyConstraint to the ConstraintCollection of the DataTable object. The ConstraintCollection determines what action to take when a value in a parent table is deleted or updated.

http://msdn.microsoft.com/en-us/library/dz0az7c7.aspx