That line says that if a SQL value has type ARRAY or MULTISET, we will use an implementation that is some subclass of java.util.List. That’s fine. It’s useful that the representation has a deterministic ordering, even if the MULTISET type doesn’t require it. Neither type requires us to eliminate or disallow duplicate values.
> On Jul 14, 2026, at 7:55 AM, Andrei Mereuta via dev <[email protected]> > wrote: > > Dear Calcite Maintainers, > > I have come across the following line of code > <https://github.com/apache/calcite/blob/2bdc6af448693c81da3e16208b1af2325fee1d2a/core/src/main/java/org/apache/calcite/jdbc/JavaTypeFactoryImpl.java#L259> > which > basically treats any java set as list. Is there a specific reason for this? > I would like to propose to use a different abstraction, namely > `Collection`. Curious of what you think. > > Best regards, > Andrew Mereuta
