Datasource Won't Update On Delete

hi,





I have a dataadaptor which i use to fill a dataset. I can do this no problems. But if I delete a row from the dataset and update the adaptor again, nothing gets changed in my source database. Does anyone know why this is?





here's my code for my dataadaptor:


SqlConnection conn = new SqlConnection(connectionString);


SqlDataAdapter adapter = new SqlDataAdapter();


adapter.SelectCommand = new SqlCommand("select * from tblExtRef", conn);


adapter.SelectCommand.Connection = conn;





SqlParameter parm;


SqlCommand cmd;


cmd = new SqlCommand("DELETE FROM tblextref WHERE extrefid = @extrefid",conn);


parm = cmd.Parameters.Add("@extrefid", SqlDbType.Int , 40, "extrefid");


parm.SourceColumn = "ExtRefid";


//parm.SourceVersion = DataRowVersion.Original;


//parm.Direction = ParameterDirection.InputOutput;


//SourceVersion = DataRowVersion.Original;


adapter.DeleteCommand = cmd;