It seems 3rd party plug-ins can cause them. I found another PDO exception on Line 723 discussed and it suggested "contact software developer" or "Site restore" to before the glitch occurred. Or manually fix it in the code itself. It could be an extra character or a misspelled word. I won't pretend to know much, but I do know a single coding error, like trying to add autoplay on your profile can render the edit page inaccessible unless you reset the site to before you fucked it up.
I haven't done any programming for a couple decades, and never php, but the code is very similar to c, anyway...
That's one possibility anyway.
Edit : or a non-technical solution like a 'rollback' or something, but it's been a long time for me, and I'm not certain what all the options are.
Edit : and of course nowadays Google and a little research is always a viable approach to supplement. I actually had a quick look maybe a couple days ago and it said something about a mix-up between a string literal and a number value which would be something like the difference between "variable" and variable.
Talk is cheap though, it's quite another thing to actually have to fix the problem.
Some sites were all but abandoned by staff, and I assume some were just becoming obsolete like old software. 2009 doesn't seem too awful old though.
Well, maybe, someone was trying to get in but, good Jesus, that would be some chronic asshurt at this point.If so, it's par for the course for spineless religious asshurt and/or some faithlike bubble being popped. Usually when the fruity little views are trashed. Too stereotypical to be direct with why their angry.
Humorous how "Satanists" get that same "Atheism is a religious belief too" panty twist all Jesus Is Love Christians do when given the same types of arguments.
I even remember once years ago when I was pissed at someone and went into the driver file for the modem and changed something because I knew it would fuck everything up, and the way they resolved that, eventually, was by reverting to a previous restore point.
I don't even think you need access to the code itself. Oxwall is old and you really can't rule out someone adding something to a blog that rendered the data base unusable the same way certain links (social media ones) jack the newsfeed and lock most of the site up.