This post will be mainly about a way to migrate content with alembic. If you are searching for information on how to get started with alembic read the linked blog post about that. You may have come to a point at some time where you had to update your data because of changes in the structure. An example might be that you only had a name column, but now need a finer grain of control and thus want to split up the name column in two columns. With a standard alembic migration you won’t get far, but don’t worry, this is not impossible. First I will give you an example to work with. Let’s use the example we had before (it might be an address book), which might include the following code: 1 2 3 4 5 6 7 8 9 10 from sqlalchemy import Column, Integer, String from sqlalchemy.ext.declarative import declarative_base Base = declarative_base() class Contact(Base): __tablename__ = 'contacts' id = Column(Integer, primary_key=True) name = Column(String(length=100)) So we create all this and set it up (for a detailed description of what I did when, you can check out the commit history of the github repository for this post). Now we just create some data to actually make the whole thing work, I used this code for it: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 sballmer = Contact('Steve Ballmer') sjobs = Contact('Steve Jobs') mzuckerberg = Contact('Mark Zuckerberg') from sqlalchemy import create_engine from sqlalchemy.orm import sessionmaker engine = create_engine( 'mysql://alexander:@localhost/alembic_content_migration_example' ) Session = sessionmaker(bind=engine) session = Session() session.add(sballmer) session.add(sjobs) session.add(mzuckerberg) session.commit() This is also what the function create_example_contacts in database.py does, just in case you want to use it. So now we have some data and we realize that it actually would be better to have saved the contact names as first- and lastname. Well, damn! So what now? So I adjust the model as follows: 1 2 3 4 5 class