endSetup() methods are commonly used for schema and data setup scripts by many developers. But do we actually need to call these methods for every install or upgrade script implementation? The correct answer may be quite unexpected. :) No, we don’t need to use these methods by default in our setup scripts in most cases. Let’s find out why.
One of the things that Magento first version lacked was an ability to clean up module data from the database upon its removal. This is a common situation when you uninstall an extension but all the related data remains in the database. You can only get rid of it manually. It is inconvenient especially if the module has created a bunch of new tables, custom attributes, system configurations etc. In this case, an automatic removal tool of such data would be very useful.
In Magento 2 there is a great feature, which allows to create an uninstall script for your module. Let’s find out how it works.