I have run into the same issue as this thread which was closed without resolution.
The error message in the events (view) tab: WordPress database 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]
The site is for a group who owns several movie theaters. Each event is a showtime at its respective venue. We have input 420 showtimes so far I expect to have several thousand entries with in the next few months. We can no longer sort or apply filters to the event display to check our work. Please advise.
The full error message contains the query string, if you need that I can provide it. I am open to workflow suggestions to reduce the number of posts needed.