I've setup a Craft 3 site for a client and we are seeing the strangest thing where pages are just disappearing. Best we can tell no-one has deleted the entry, but we get a 404 on the front-end and it is not showing up on the back-end, even under "Trashed". What is weird is that when I re-create the page I can't use the same slug so it seems like it is still in the database. I've tried querying the database and I can see rows in the elements_sites table with that uri, but I don't know enough about the data scheme to tell where the disconnect is or tables to look at to determine which is the "live" version. One other note that may be related is several pages disappeared that were all sub-pages to a parent page (but the parent page is still there on the site)
Here is a query I ran for one of the pages that is missing:
Any suggestions for how to figure out what is happening or a query to run to determine which pages are live and where the disconnect may be for those pages?