DataColumn
							tmpDataColumn;

						SQLText="MasterTable";
						ds.Tables.Add(SQLText);
						tmpDataColumn=ds.Tables[SQLText].Columns.Add("Id",typeof(long));
						tmpDataColumn.AllowDBNull=false;
						tmpDataColumn.Unique=true;
						tmpDataColumn.AutoIncrement=true;
						tmpDataColumn.AutoIncrementSeed=- 1 ;
						tmpDataColumn.AutoIncrementStep=- 1 ;
						ds.Tables[SQLText].Columns.Add("Name",typeof(string));
						ds.Tables[SQLText].PrimaryKey=new DataColumn[]{ds.Tables[SQLText].Columns["Id"]};

						SQLText="DetailsTable";
						ds.Tables.Add(SQLText);
						tmpDataColumn=ds.Tables[SQLText].Columns.Add("Id",typeof(long));
						tmpDataColumn.AllowDBNull=false;
						tmpDataColumn.Unique=true;
						tmpDataColumn.AutoIncrement=true;
						tmpDataColumn.AutoIncrementSeed=- 1 ;
						tmpDataColumn.AutoIncrementStep=- 1 ;
						ds.Tables[SQLText].Columns.Add("MasterId",typeof(long));
						ds.Tables[SQLText].Columns.Add("Sum",typeof(decimal));
						ds.Tables[SQLText].PrimaryKey=new DataColumn[]{ds.Tables[SQLText].Columns["Id"],ds.Tables[SQLText].Columns["MasterId"]};

						string
							RelationName="Master_Details";
						
						ForeignKeyConstraint
							_fk_;

						ds.Tables[SQLText].Constraints.Add(_fk_=new ForeignKeyConstraint("fk"+RelationName,ds.Tables["MasterTable"].Columns["Id"],ds.Tables["DetailsTable"].Columns["MasterId"]));
						_fk_.UpdateRule=Rule.Cascade;
						_fk_.DeleteRule=Rule.Cascade;
						ds.Relations.Add(RelationName,ds.Tables["MasterTable"].Columns["Id"],ds.Tables["DetailsTable"].Columns["MasterId"]);
						SQLText="MasterTable";
						ds.Tables[SQLText].Columns.Add("TotalSum",typeof(decimal),"Sum(Child("+RelationName+").Sum)");

ds.Tables["MasterTable"].Rows[ 0 ]["Id"]= 13 ;

ds.Tables["MasterTable"].Rows[ 0 ]["Id"]= 13 ;
ds.Tables["MasterTable"].Columns["TotalSum"].Expression="Sum(Child("+RelationName+").Sum)";