Using Teiid 9.2.2 with postgresql, I issue a query structured like this:
All queries are from a single database.
This query does not give back the expected result.
In the plan, I see the query printed with no parenthesis around the unions:
a UNION ALL b UNION ALL c INTERSECT d
This gives the same result as the query submitted with no parens in it (the intersect of c and d is unioned with a union b.
The expepeted result is to preserve the paren so that the intersect is performed against the union of all three tables.
As a note, using UNION instead of UNION ALL did not preserve the parens, either.