I had never seen this error before, so I thought I would just take a second to post it in case anyone tries to Google it. Luckily, my query was extremely small and so the error was obvious from a quick review of the SQL; but, in a large query this might not be readily apparent. Here's the kind of query I was running in MySQL:
UPDATE [user] SET is_active = 1 WHERE u.id = 4
Can you see what the problem is? My WHERE clause uses an aliased table name, but my UPDATE clause did not alias the table. I am so used to using aliased tables that when I saw the error, it didn't even occur to me that the aliasing itself was causing the issue. Once I removed the alias "u.", the query worked fine.
Again, a really minor note, but I thought it might help someone.
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