We had a problem after upgrading to PI Vision 2019 for SQL server table queries. See Image below.
The other server with PI Vision 2017 R2 which is a replicate to this.
Server 1 - Upgraded PI Vision 2019
Server 2 - PI Vision 2017 R2
Is it the SQL server? PI AF Database is Synchronized for Server 1 and 2 with Always On HIgh Availability.