[R] my RMySQL connections are so SLOW
ernesto at ipimar.pt
Mon May 5 12:35:27 CEST 2003
On Mon, 2003-05-05 at 11:03, Laurent Faisnel wrote:
> Ernesto Jardim wrote:
> >On Mon, 2003-05-05 at 09:56, Laurent Faisnel wrote:
> >>Hi all,
> >>I'm using the latest RMySQL to send requests to a MySQL database (which
> >>is quite small for the time - let's say 20 tables with a total of 1000
> >>rows), and this should be part of a whole decisionnal system. It
> >>produces results which are displayed on a website, and therefore I need
> >>fast results (the database being quite small, I think this must be
> >>possible !).
> >>Unfortunately, a simple request to the database, and R needs more than
> >>10 seconds. Even dbListTables() takes a long while. Imagine the problem
> >>with more data ! Can I hope something better with RMySQL ? Did anyone
> >>have the same problem ?
> >>If RMySQL (or is it MySQL's fault ?) is so slow, I could replace MySQL
> >>with Postgres, but this would imply a lot of extra work. R is perhaps
> >>very slow anyway ? Any piece of advice ?
> >>R-help at stat.math.ethz.ch mailing list
> >Have you tried to run the sql statement in mysql to check if the problem
> >is really in RMySQL ? MySQL databases can be very slow if you don't
> >index the tables.
> I'll try at once. My tables are not indexed. But I thought this could
> not explain everything. Anyway, a few tests will be profitable. Thanks
I've had some surprises with table indexing ... The documentation says
it can be 100 times faster!
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