Xiaodong Jin wrote:
> how to realize the following SQL command in R?
>
> select distinct A, B, count(C)
> from TABLE
> group by A, B
> ;
> quit;
>
> Best Regards
You don't say which database you are using, but I have found RODBC to be
very effective.
library("RODBC")
Have a look at odbcConnect(), and sqlQuery(). It is quite
straightforward; even I managed to use it!
Otherwise try help.search("sql") which provides links to many other,
database-specific packages.
Mark
--
Dr. Mark Wardle
Clinical research fellow and Specialist Registrar in Neurology,
C2-B2 link, Cardiff University, Heath Park, CARDIFF, CF14 4XN. UK
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