[SOLVED] ownCloud to Nextcloud migration - oc_accounts foreign key constraint fails

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8

Hello
I have the same issue,
OCloud was installed (10.14.0)
i try to upgrade Nextcloud
(using my old OC config/data files)
php ./occ upgrade

So I try

SELECT TABLE_NAME,COLUMN_NAME,CONSTRAINT_NAME, REFERENCED_TABLE_NAME,REFERENCED_COLUMN_NAME
    -> FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
    -> WHERE REFERENCED_TABLE_SCHEMA = 'owncloud' AND REFERENCED_TABLE_NAME = 'oc_accounts';

But no line affected.
How to reproduce ?

[EDIT]

SELECT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE WHERE REFERENCED_TABLE_SCHEMA = 'serendipvspip'

from Migration owncloud 10.2.1 to NC 12.0.12 An exception occurred while executing 'DROP TABLE oc_accounts' - #5 by sneo
output some thing… 2 FK_…
[/EDIT]

Thanks for the clues (and hope)