Thanks Metin for your suggestion.
The reason why I am using timestamp is a limitation with SQL Server. In order to check if some user changed the record, VFP includes in the WHERE clause for UPDATE, the ModifiedFields, the problem you have if you change a Memo field, in this case SQL doesn´t allow text fields in where clause using "=". So, in case I have to turn off the option to "Compare Memo Field", then VFP will not include memo fields in where clause. But, if I do that, VFP allow you to overwrite the changes made by other user. That´s why we decided to use timestamp fields.

It is make sense for you?