Hi Jorge,

I assume you're using SQL Server!
The error VFP is giving to you cannot be solved with SET NULL ..., because the problem becomes from SQL Server. You must "uncheck" the ALLOW NULLS column at all fields of your table (by the way, give always a DEFAULT value too). It sounds terrible "unchecking" for all fields, but you can do it by code, when you are creating your table.
Like you can check the UPDATABLE column at the creation of your views (use DBSETPROP()).

Say anything if you need.

Good luck,

Ricardo