Hi,
I recently updated von 1.10 to 1.10.4 and now 1.11.0. The update to 1.10.4 was not so smooth so I was eager to get to 1.11.0. In general it works ok-ish but we have some issues wih advanced searches.
The count of tickets is not right (e.g. 9 tickets result, but stats show "Showing 1 - 50 of about 500") or other searches are not really working out. In geral I see a lot of errors #1064, most of them have a systax error.

Example:
SELECT COUNT(DISTINCT CASE WHEN A1.dept_id = 2 THEN A1.ticket_id END) AS q90, COUNT(DISTINCT CASE WHEN THEN A1.ticket_id END) AS q95, COUNT(DISTINCT CASE WHEN A1.dept_id = 2 THEN A1.ticket_id END) AS q96, COUNT(DISTINCT CASE WHEN A1.dept_id = 2 THEN A1.ticket_id END) AS q99, COUNT(DISTINCT CASE WHEN A1.created >= '2018-09-18 00:00:00' AND A1.created

As you can see here easily (hrhr) the error is a missing statement in CASE WHEN ... THEN clause. The first one works, but the second one is missing this statement (--> CASE WHEN THEN A1.ticket_id END).

I have a bunchload more examples, alswas a WHEN THEN is empty in the error message.

Any pointer, where to dig further? Is something missing in the DB? Maybe an inclomplete migration?

Environment:
Ubuntu 18.04 "latest"
- mariadb-server-10.1 (10.1.38-0ubuntu0.18.04.1)
- apache2 (2.4.29-1ubuntu4.5)
- php7.2 (7.2.10-0ubuntu0.18.04.1)