June 2017

Clean up database pollution from the migrate Drupal module

I'm working on a large, complex migration from Drupal 7 to Drupal 8 right now. One thing I noticed is that the migrate modules pollute the database with an unreal number of tables which allow migrations to be re-run, etc. Well if you don't need that, here's how to remove these tables. Currently the migrate modules don't clean up after themselves. Put this in a custom module or PHP script that has bootstrapped Drupal. Note this code only works in Drupal 8. Shown is a .install file for a custom module. If you uninstall the custom module, it will run the cleanup: