hi,this is my first participation on this forum, I'm new to lazarus and pretend to write a small DB application using SQLite and SQLdb.Did the http://wiki.freepascal.org/Lazarus_Database_Overview and the SQLdb TutorialX series (a very sweet idea but lacking the minimum to achieve a functional DB app) and still have many questions:
How to validate a record before update to the database?
How to cancel that update, being an existing record update or an a addition, if the validation fails?
How to cancel a navigation to another record if there are pending updates and the validation fails?
If there are calculated fields that depend on the user input, where do I make those calculations prior to the post?
If there are calculated fields that need to be, well, 'calculated' when the record changes, where do I do that?
What is the order of the events?
Thank you in advance for your help.