Database Migration Algorithm

UML Diagram of Database Migration Interface

Proposed Tasks (Before First Meeting)

• Create the Interface Class
• Create file for noting the target version of the database
  • could be a json file with a description of the changes -Adding table to database to note the current version of the database
  • (we probably want to use this as our first test case for updating and rollback!)
  • Name of Table: deploy_current_database_version
  • Columns: Id column, version_number column, deployed_on timestamp, description_of_version_changes (read from json)
• Organize Files for Database Migration
  • Make a directory within tools for the database version folders to be stored and move the static version file inside of it as well
• Edit init_db.py
  • Init_db already checks if the database exists and if it doesn’t instantiates it.
  • person who is doing this can also brainstorm new names for the file (maybe migrate_db.py?)
  • Add the logic for checking the database version.
    • Read current version from database
    • Read the target version from the file.
    • Update or Rollback as needed, updating the version file as you go.
    • Stop when the correct version is reached.
• Finish Script To Add API Account
  • Parameterization of query
  • Implementing both methods in interface

Notes (form first meeting discussing Database Migration)

• absolutely use transactions for the update methods (so that things that don't work will automatically not make it to the database)
• rollback is just for purposeful user rollback not automatic rollback if update method fails
• for versions of the database major.minor
  • major = adding tables or editing scheme
  • minor = adding data/users/anything else