Data Base isn't updated when I use DataAdapter

dataSet.Tables[0][0].X = 9; dataAdapter.Update(dataSet); What happesn here, that I don't understand, is that after de firs line, DataRowState property for dataSet.Tables[0][0] is Unchanged, so, obviously, after line 2 executes the database is not updated. I have no idea why it is thst this happens. The dataSet is the dataSource of a DataGrid, but I suppose that has nothing to do with anything.

I know the concept of Dateset and DataAdapter, that's why I'm burry because when I change something in a Dataset when I will update that with the DataAdapter asociated. The DataAdapter verify if the dataset has some change and aply the SelectCommand, InsertCommand or DeleteCommand for update de Data Base. The problem is that when I change the DataSet the property of him is UNCHANGED when it has to be CHANGED. What happen with that property? Conozco el concepto de DataSet y DataAdapter, es por eso que me preocupo porque cuando yo realizo un cambio en el dataSet y al dataAdapter asociado con el le invoco el metodo Update, deben reflejarse los cambios en la Base de Datos mediante la realizaci'on de SelectCommand, InsertCommand o DeleteCommand si son necesarios, pero el Problema es que no son reflejados estos cambios porque la propiedad de la Fila ROWSTATE tiene valor UNCHANGED, es decir que no se cambio a CHANGED cuando hice los cambios. Por tanto no pasa nada en la Base de Datos. A qu'e se puede deber esto?

this thing shouldn't even compile. Where did you find this code? Did you make it up? please check msdn and understand the concept of dataset and data adapter. then if you have questions, ask a question.