Please note that patch[1] was merged.
This patch will prevent(with a detailed ERROR[2]) any attempt to modify an existing DB upgrade script since this may lead to upgrade problems.
The correct way to change something in the database is a new upgrade script.
In a case that the upgrade script must be changed, this can be forced by adding a special keyword[3] to your commit header.

Please see [1] description for details.

If you have any questions, please let me know.

[1] https://gerrit.ovirt.org/#/c/96421/
[2] [ERROR] : Changing an existing upgrade script is dangerous and can cause upgrade problems,
            if you are doing that in purpose and sure that there is no other way to fix the issue you
            are working on, please add the key 'Allow-db-upgrade-script-changes:Yes' to your patch commit message."
[3] "Allow-db-upgrade-script-changes:Yes"


Eli Mesika