Document NullifyOrphanRunnerIdOnCiBuilds migration failure
What does this MR do and why?
Related to #415724 (closed)
In %14.9 we've added a background migration(that was not completed) and in %15.10 we've changed the database primary key for the table which prevents ActiveRecord from generating a valid SQL query. If someone upgrades from 14.9 to 15.11(which is the hard stop to complete all background migrations) this migration could fail.
More details on the events timeline: #415724 (comment 1447201715)
How to set up and validate locally
Numbered steps to set up and validate the change are strongly suggested.
MR acceptance checklist
This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.
-
I have evaluated the MR acceptance checklist for this MR.
Edited by Marius Bobin