This exception is thrown if you try to insert a null value into a column that has DataColumn.AllowDBNull set to false . public class NoNullAllowedException : DataException { // Public Constructors public NoNullAllowedException ( ); public NoNullAllowedException ( string s ); // Protected Constructors protected NoNullAllowedException (System.Runtime.Serialization.SerializationInfo info , System.Runtime.Serialization.StreamingContext context ); } HierarchySystem.Object System.Exception(System.Runtime.Serialization.ISerializable) System.SystemException DataException NoNullAllowedException |