[R] RMySQL loading error

[Prof Brian Ripley]

On Thu, 9 Aug 2007, Clara Anton wrote:

> Hi,
>
> I am having problems loading RMySQL.
>
> I am using MySQL 5.0,  R version 2.5.1, and RMySQL with Windows XP.

More exact versions would be helpful.

> When I try to load rMySQL I get the following error:
>
> > require(RMySQL)
> Loading required package: RMySQL
> Error in dyn.load(x, as.logical(local), as.logical(now)) :
>    unable to load shared library
> 'C:/PROGRA~1/R/R-25~1.1/library/RMySQL/libs/RMySQL.dll':
>  LoadLibrary failure:  Invalid access to memory location.
>
>
> I did not get any errors while installing MySQL or RMySQL. It seems that
> there are other people with similar problems, although I could not find
> any hint on how to try to solve the problem.

It is there, unfortunately along with a lot of uniformed speculation.

> Any help, hint or advice would be greatly appreciated.

The most likely solution is to update (or downdate) your MySQL.  You 
possibly got RMySQL from the CRAN Extras site, and if so this is covered 
in the ReadMe there:

   The build of RMySQL_0.6-0 is known to work with MySQL 5.0.21 and 5.0.45,
   and known not to work (it crashes on startup) with 5.0.41.

Usually the message is the one you show, but I have seen R crash.  The 
issue is the MySQL client DLL: that from 5.0.21 or 5.0.45 works in 5.0.41.

All the reports of problems I have seen are for MySQL versions strictly 
between 5.0.21 and 5.0.45.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595