Data and Schema Patches

A new way to manage data and schema updates in Magento 2, these are preferred over install and setup script.

Magento Dev Docs

Similar to install scripts, patches are applied during setup:upgrade, unlike install scripts they do not require module versioning.

Patches can only be applied once and are stored in the patch_list table, when developing you can remove the relevant line from this table and run setup:upgrade to apply the patch multiple times.