code: async function tryExample () {
  
    // Migration scripts
    const migrations = {
  
      // Called only if no migration has ever executed
      async 'none' (db) {
        const {User} = db.resources
  
        // Migration scripts
        await User.each(async (user) => {
          const {username} = user
          await user.update({name: username, username: null})
        })
        /* ... */
  
        await db.updateVersion('1.0.0') // Update to next version
      },
  
      async '1.0.0' (db) {
        /* ... */
        await db.updateVersion('1.0.1')
      }
    }
    await db.migrate(migrations)
  }
docs: Using defined database