SQL Queries from Multiple Servers
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
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