Some initial thoughts on the matter:
- Verify that you have valid database backups in place before changing a live environment.
- Have a rollback plan setup ahead of time in case something goes wrong so you can recover to the point before the changes without any loss of data.
- Test your changes in a non-production environment prior to attempting anything with a live database, including testing your rollback plan.
- Have a verification plan in place so after your changes go out you know ahead of time how to verify that they were successful. Be prepared to make a "go or no-go" call during or after the verification steps have been run.
- Consider whether you need to take the database offline during the changes, what impacts that might have on user applications and how you might need to communicate the outage is end-users will be affected. If you cannot take the database offline consider how that will affect your rollback plan.
There are no special teachers of virtue, because virtue is taught by the whole community. --Plato