Thanks a lot Julian, this is very helpful! On Tue, Jan 17, 2017 at 10:35 PM, Julian Hyde <jhyde.apa...@gmail.com> wrote:
> I think what you’re after is how to convert a predicate, say > > select * from emp > where (empno = 100 or empno between 200 and 1000) > and empno not between 150 and 400 > > into a set of ranges > > [100], (400, 1000] > > Actually we don’t have that in Calcite, but note that literal values of > all data types are Comparable and that Guava has an excellent RangeSet > class. > > For the Druid adapter we needed to convert expressions like > > EXTRACT(YEAR FROM t) = 2016 > AND EXTRACT(MONTH FROM t) BETWEEN 5 and 7 > > into > > t BETWEEN ‘2016-05-01’ AND ‘2016-07-31’ > > and for that we created DateRangeRules (see https://issues.apache.org/ > jira/browse/CALCITE-1334 <https://issues.apache.org/ > jira/browse/CALCITE-1334>). You’ll notice that DateRangeRules also makes > extensive use of RangeSet internally. > > Julian > > > > On Jan 16, 2017, at 5:21 PM, Ambud Sharma <asharma52...@gmail.com> > wrote: > > > > Hi, > > > > I am trying use calcite and develop a custom adapter. I have implemented > > the SPI and able to get basic enumerator to work with a simple select > query > > and no where clause. > > > > Trying to understand how to convert operators to range scan and push them > > to the underlying data source. > > > > Should it be a rule or a visitor if yes how do you subset the nodes so > that > > only the range scannable entity is delivered to the converter. A link to > a > > working example would help. > > > > The data source has range scan capability and I can make a method call to > > it. > > > > Thanks and regards, > > Ambud > >
