The Magento 2 Merchant Beta release (1.0.0-beta) includes a schema update that requires you to uninstall the Magento software and reinstall it.

The reason is that all modules in Merchant Beta are version 2.0.0. The update affected all data and schema in the Magento 2 database.

To update to the Merchant Beta release:

1. Back up your Magento 2 database, file system, and media files.
2. Uninstall the Magento software.
3. Upgrade the Magento 2 codebase as follows:
   1. Log in to your Magento server as a user with permissions to modify files in the Magento file system (for example, the web server user).
   2. Change to the <your Magento install dir> directory.
   3. Save a copy of composer.json.
   4. Update your local repository to get the latest code:

      git pull origin develop

      If git pull origin develop fails, see troubleshooting.

   5. Diff and merge your saved copy of composer.json with new composer.json provided with Merchant Beta.
   6. Enter composer update.
   7. Clear var directory contents:

      rm -rf var/generation/* var/cache/*

4. Install the Magento 2 software from the command line or Setup Wizard.
5. Verify the installation.