I'm just starting to use subversion and if I copy the trunk to a branch to work on some new design and features. Should I create a copy of the production database. Connect to this new development database from my branch files (Zend project). Make any changes needed, such as adding new fields creating new tables etc. Then when ready to merge the branch to the trunk. Update the production db with the development db changes? If so what are some good methods to merge or update the production database? Thanks
Schema Sync may be useful for you here. It will generate a list of all the DDL needed to modify the one database to have a schema similar to another.
If you hare making major changes besides just adding a couple fields, this may not be very useful.
What you may need to do is simply write a program/script yourself to do the upgrade. Or build yourself some kind of upgrade script that will examine the database and make changes as needed.