[R] RODBC

[Emmanuel Charpentier]

I saw in the R-digest a thread about RODBC.

1) I think that this package is *extremely* valuable : it fulfills a need
quite important in the case of iterative (e. g. periodic) analyses. No need to
periodically return to your data and re-dumping them ...

2) The current version has a serious bug if your datasets has missing numeric
values. M. Lapsley, the original author, is aware of it, but has had no time
yet to look at it ...

I looked into the source to no avail. I'll have to dive in ODBC library
mysteries (which are pure Swahili to me ...), and did not yet had time for
this.

<OffTheTopOfMyHeadIDontHaveTheFilesOnHand>
In interim, you can uncomment the old (much less efficient) of the odbcQuery
routine, which does *not* exhibit this bug. Data are correct, speed seriously
sucks ...
</OffTheTopOfMyHeadIDontHaveTheFilesOnHand>

3) If you happen to use PostgreSQL, the RPgSql package (also on CRAN) is much
more interesting : it allows direct access to PostgreSQL classes (tables) as R
objects, ensuring that any R access is done to up-to-date data.

Of course, OTOH, if you happen to trash your R data-access-objects, your
original data are gone for good. Caveat emptor ...

4) IMNSHO, the future lies somewhere in the (hypothetical) fusion of these two
package : direct access to ODBC objects would be perfect (and might seriously
alleviate problems due to the R static memory allocation model, which is an
EPITA ...).

Hope this helps,

					Emmanuel Charpentier

--
Emmanuel Charpentier			Tel :		+33-01 40 27 35 98
Secrétariat scientifique du CEDIT	Fax :		+33-01 40 27 55 65
Direction de la Politique Médicale // Assistance Publique - Hôpitaux de Paris
3, Avenue Victoria // F-75004 Paris /// France
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-help-request at stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._