Appwrite schema migrations

Hi team, I'm new to Appwrite and wanted to read up on how database schema migrations are handled. I did see the cli collections pull and push commands however, I didn't see how the collections manage to transfer data to the new schema ie if a column were to be renamed, will the previous rows be copied into the new columns. It's not clear to me as there are no explicit sql commands that are present. Please point me to the right place in the docs to undertand this better. Thanks!