While working on https://issues.apache.org/jira/browse/FLINK-4542 I realized that most of the multiset operations do not work and skipped in tests with
. So here I propose to fix it.
Here it is my branch with fixes and tests
Currently it is done for
may be the only one which is not done yet is FUSION
by the way I have a question: is it ok that default case for MULTISET INTERSECT/UNION /EXCEPT is DISTINCT (here ) ? At the same time Oracle behaves in the opposite way (e.g. here https://docs.oracle.com/cd/B19306_01/server.102/b14200/operators006.htm)
I can make a PR if nobody minds