PHP Fatal error: Uncaught Exception: DB Error: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay Query:

  • Application Version - OJS 3.2.03
  • Description of issue - When attempting to add a reviewer to a submission, we get a Failed AJAX request error. Checking the error_log, I found this line “PHP Fatal error: Uncaught Exception: DB Error: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET MAX_JOIN_SIZE=# if the SELECT is okay Query:” Right after is a bunch of Left Joins. the file is lib/pkp/classes/db/DAO.inc.php Line 703.
  • Steps you took leading up to the issue - attempted to add a reviewer to a submission.

I have not been able to find any information that could help, although I’ve tried several of the options in here where someone had a similar Failed AJAX request.

See a similar thread here:

If you are able to access your database directly, the link describes a query you can run to find out what you MAX_JOIN_SIZE setting is for the database.

I would be curious to know how many users you have in your database, what your MAX_JOIN_SIZE is, and what the full SQL query is which failed.