I don’t recall interval literals being discussed on the Calcite list. We do support interval literals of the standard types (day-to-second or year-to-month) but we don’t support interval literals (or interval values) of month-to-day type. I think there’s a good reason that that kind of literal isn’t in standard SQL - it is not very well-defined how to add such an interval to a date (or how to create one by subtracting two dates).
There are a lot of assumptions-on-assumptions in this case. It would be helpful if there were JIRA cases were logged for missing functionality (even if we don’t end up adding that functionality). Julian > On Feb 2, 2016, at 7:33 AM, Jason Altekruse <altekruseja...@gmail.com> wrote: > > I made this change. It was a bit of a hack to re-use the non-deterministic > property as an indication if a function could be folded into a constant. > > If you look at the definition of that list of NON_REDUCIBLE_TYPES constant, > explanations are given for why given types are included. > > The problem with the INTERVAL type is that Calcite did not allow creating a > literal for this format. I believe this was intentional, so I didn't bother > opening a Calcite JIRA. The issue is that our interval type spans across > months and days, which I wasn't even sure how to interpret. I could not > find an example of this type in other databases, see docs linked for > examples in SQL Server and Oracle. [1] [2] Both of these systems support > intervals that span across years and months or days/millis, and both of > these Drill types are supported by the constant folding rule. > > [1] - > http://docs.oracle.com/cd/E11882_01/server.112/e41084/sql_elements001.htm#SQLRF30020 > [2] - https://msdn.microsoft.com/en-us/library/ms716506%28v=vs.85%29.aspx > > On Tue, Feb 2, 2016 at 6:11 AM, Jacques Nadeau <jacq...@dremio.com> wrote: > >> What jira was this change added with? >> On Feb 1, 2016 11:42 PM, "Hsuan Yi Chu" <hyi...@maprtech.com> wrote: >> >>> All the variants of Negative DrillFuncHolder are supposed to be >>> deterministic. However, when they are being registered >>> into DrillOperatorTable, there is a if-statement: >>> >>> >>> https://github.com/apache/drill/blob/master/exec/java-exec/src/main/java/org/apache/drill/exec/expr/fn/DrillFunctionRegistry.java#L116 >>> >>> which claims DrillFuncHolder being non-deterministic when return type is >>> Interval. Why it is necessary to have this if-condition? >>> >>> ------------------------- >>> >>> Making DrillFuncHolder non-deterministic will prevent partition-pruing or >>> constant folding from happening. >>> >>
