For many customization projects, the first task is to extend
the database so that it supports the other UI or API changes that
you make later.
Review this topic for the following information:
- Important guidelines about what you can and cannot change in the
database.
- Information about modifying APIs. If you modify database tables
so that any APIs are impacted, you must extend the templates of those
APIs or you cannot store or retrieve data from the database. This
step is required if table modifications impact an API.