Add support for long integers

[russellpierce]

Feature request. Long integers are a common data-type in today's DBs, but R still lacks a native way to represent integers larger than 2147483647. Could a dependency be added to RJDBC that would use https://cran.r-project.org/web/packages/bit64/index.html that would allow data to come from the attached DBs in the form of an integer rather than having to cast them to character in the query and convert them back into long integers once they are in R?

[s-u]

Can you give an actual example? There should be no need for casting, it all depends on the representation supported by the driver. We can always fetch it as string and post-process, 1c6399c add automatic support for the at least on retrieval if the driver tags it appropriately with one of the types.