Whenever I attempt to add or edit a page in Structure, I get the following error:
A Database Error Occurred
Error Number: 1064
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' listing_cid = 0, hidden = '' WHERE entry_id = 456' at line 1
UPDATE exp_structure SET parent_id = , listing_cid = 0, hidden = '' WHERE entry_id = 456
Line Number: 2993
It doesn't seem to matter what's on the page, how complicated it is, or how old it is.
The site's running on EE v2.11.7 and Structure v3.3.19. Attempting to use Structure's "Debug" mode did nothing.
Any ideas as to what could be causing this? The only recent major change to the site was upgrading to a newer version of PHP. Hopefully that's not the culprit, because that was required to fix some compatibility issues with a different add-on.