[R] SQL Queries from Multiple Servers

[Mark Wardle]

Hi.

Depending on your requirements, one option would be to do the join in
R using merge()

If you wish to run SQL joins across multiple databases, then it is not
an R problem but a database problem. For a quick solution, I would
write scripts that bring all your data together into one database
(could be written in any scripting language, and of course R) and then
process from there.

Bw

Mark

2009/5/13 Tom Schenk Jr <tomschenkjr at gmail.com>:
> I use RODBC as my conduit from R to SQL. It works well when the tables are
> stored on one channel, e.g.,
>
> channel <- odbcConnect("data_base_01", uid="....", dsn="....")
>
> However, I often need to match tables across multiple databases, e.g.,
> "data_base_01" and "data_base_02". However, odbcConnect() appears limited
> insofar as you may only query from tables within a single channel, e.g.,
> database. I do not have access to write and create new tables on the SQL
> servers, which is a possible solution (e.g., copy all tables into a single
> database).
>
> Is there any way, in RODBC or another R-friendly SQL package, to perform SQL
> operations across multiple databases?
>
> Warm regards.
>
> --
> Tom Schenk Jr.
> tomschenkjr at gmail.com
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
>



-- 
Dr. Mark Wardle
Specialist registrar, Neurology
Cardiff, UK