[teiid-issues] [JBoss JIRA] (TEIID-5783) OUTER JOIN yields wrong results when used with GROUP BY, CASE and COUNT DISTINCT

OUTER JOIN yields wrong results when used with GROUP BY, CASE and COUNT DISTINCT -------------------------------------------------------------------------------- Key: TEIID-5783 URL: https://issues.jboss.org/browse/TEIID-5783 Project: Teiid Issue Type: Bug Components: Query Engine Affects Versions: 12.0 Environment: teiid-12.0.0 on WildFly Full 14.0.1.Final (WildFly Core 6.0.2.Final) Reporter: Dmitrii Pogorelov Assignee: Steven Hawkins Priority: Blocker Fix For: 12.2.2, 12.3, 12.1.2 Attachments: test1.csv, test2.csv Some queries that involve an OUTER JOIN between objects from different data sources, a GROUP BY with a CASE statement and a COUNT DISTINCT yield inconsistent results on a SELECT expression which is identical to the GROUP BY expression with CASE. * Reproduced in combination of <File> LEFT JOIN <MySQL> and <File> LEFT JOIN <MS SQL> and the same for the other OUTER JOIN variants. * screenshot for the different queries are attached * sample data for reproduction is attached The same problem happens with LEFT OUTER JOIN, RIGHT OUTER JOIN and FULL OUTER JOIN.