Updating do records
When you need to update data from one table to another, consider the following rule: the data types for the source and destination fields must either match or be compatible.Sender Policy Framework (SPF) is a standard for authenticating email.
If the object does not pass validation, it will be returned anyway, but nothing will be saved to the database.
To add new records to a database you use an append query, and to delete whole records from a database you use a delete query.
Here are the similarities and differences between Find and Replace and an update query: Like the Find and Replace dialog box, an update query lets you specify which value is being replaced, and what the new value is.
Tip: Back up your database before you run an update query.
You cannot undo the results of an update query, and making a backup helps make sure that you can reverse your changes if you change your mind.