Updating from 9.1.1 to 10.2.1. SQL error

Hello, When I am trying to update following error shows.

2019-09-27T05:55:25+00:00 Doctrine\DBAL\Exception\DriverException: An exception occurred while executing ‘ALTER TABLE oc_filecache CHANGE fileid fileid BIGINT AUTO_INCREMENT NOT NULL, CHANGE parent parent BIGINT DEFAULT 0 NOT NULL’:

SQLSTATE[HY000]: General error: 2006 MySQL server has gone away

Can anybody help?

Can you check your disk space during the upgrade? I think during the upgrade a copy of the database gets created, and if it is too big your db engine might crash.
I would recommend you have a least room for a whole copy of your owncloud db during the upgrade.

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i have found this message into the search box at https://doc.owncloud.org and immediately found this documentation here:


Thank you. This virtual machine had 256 MB memory. I increased it to 2GB and upgrade went smoothly.