2989279 - Queries have different result sets but they should be the same - SAP IQ

The following is a scenario where queries have different result set, but the results should be the same.

======

1) Return 4 rows

select ta.id
from #ta ta
inner join #tb tb
on ta.id = tb.id;

id
--------------------
AAA
AAA
AAA
AAA

2) Return 4 rows

select ta.id
from #ta ta
inner join #tb tb
on ta.id =
case
when tb.id='X' then 'YYY'
when tb.id='X' then 'YYY'
else tb.id
end case;

id
--------------------
AAA
AAA
AAA
AAA

3) Does not return 4 rows

select ta.id
from #ta ta
inner join #tb tb
on ta.id =
case
when tb.id='X' then 'YYY'
else tb.id
end case;
go

 id
--------------------
AAA
AAA

• SAP IQ 15.4
• SAP IQ 16.0
• SAP IQ 16.1 

query queries different wrong result set case inner join  CR 823410 CR823410 , KBA , BC-SYB-IQ , Sybase IQ , Bug Filed