Andy Mallon ran into a weird issue with Query Store:
I tried the configuration a couple of times just to make sure it wasn’t a one-off problem. I installed the latest Cumulative Update (CU). I made sure nothing else was connected to the instance. I rebooted my machine. I restarted services. I banged my head against the wall. I asked a friend if I was insane or stupid. After confirming that I was both, my friend Aaron Bertrand (blog|twitter) confirmed it wasn’t a problem for him.
I discovered I could reproduce the problem simply by running the same simple statement that SSRS used when creating the ReportServer database. SSRS uses a non-standard collation, and specifying that collation seems to be the difference in causing the deadlock. Then I discovered that specifying ANY non-standard collation was causing the deadlock. This had nothing to do with SSRS, and everything to do with non-default collations.
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