Migrating to Owncloud 10 and PHP7.1 results in severalproblems

Hey,

i did the following search: https://github.com/owncloud/core/search?q="Unknown+column"+"fileid"&type=Issues

and found a reported and closed issues there. It seems one might provide a possible workaround: https://github.com/owncloud/core/issues/30007#issuecomment-427789626