How to: Configure Foreign-Key Constraints in a Dataset
By default, foreign-key constraints in a database are created in the generated dataset as a relation only, with the update and delete rules set to none.
You can change this behavior by editing the relationship in the dataset by using the Relation dialog box.
To configure the foreign-key constraints in a dataset
Open your dataset in the Creating and Editing Typed Datasets.
Open the Relation dialog box by double-clicking the relationship line that connects the data tables to the foreign-key constraint that is to be configured.