[teiid-issues] [JBoss JIRA] (TEIID-5937) Union All followed by except returns wrong results

 I've simplified this

Union All followed by except returns wrong results -------------------------------------------------- Key: TEIID-5937 URL: https://issues.redhat.com/browse/TEIID-5937 Project: Teiid Issue Type: Bug Components: Query Engine Affects Versions: 13.1 Reporter: Dmitrii Pogorelov Assignee: Steven Hawkins Priority: Blocker Fix For: 15.0, 13.1.2, 14.0.1 Original Estimate: 4 hours Time Spent: 5 hours, 30 minutes Remaining Estimate: 0 minutes The following queries return wrong results: {code:sql} -- <null> though should return 1 select * from views.test2 except select * from views.test1 UNION ALL select * from views.test1 except select * from views.test2 ;; -- <null> though should return 1 (select * from views.test2 except select * from views.test1 UNION ALL select * from views.test1) except select * from views.test2 ;; {code}