[R] loading data and executing queries with R and Mysql

bogdan romocea br44114 at gmail.com
Wed Jan 3 14:30:01 CET 2007

Nevermind the CPU usage, the likely problem is that your queries are
inefficient in one or more ways (i.e., you don't use indexes when you
really should - it's impossible to guess without knowing how the data
and the queries look like, which somehow you've decided are not
important enough to describe in your email). One nice reference is

> -----Original Message-----
> From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Bagatti Davide
> Sent: Wednesday, January 03, 2007 8:05 AM
> To: r-help at stat.math.ethz.ch
> Subject: [R] loading data and executing queries with R and Mysql
> Hello everyone,
> I have a problem when I execute queries using R 2.3.1 and
> MySql server 5.0.
> What I do: I load data in different csv files (every file represents a
> particular temporal step of a simulation) using Mysql query
> "load data" with
> RMySQL command DbSendQuery (but the same problem there is also using
> DbWritetable). Then I use a function where I have a lot of
> queries that
> interact with the database.
> Well, while loading data is very fast, query execution is very slow
> ...looking to Windows task manager I see that my cpu doesn't
> go to 100% of
> usage, but only at 30-45%. Looking at the processes I see Rgui.exe use
> between 0-23% and mysql-nt.exe use between 8-20% and so it is
> very slow. I
> am sure my cpu has no particular problems.
> Could you help me?
> Thanks in advance
> Davide
> 	[[alternative HTML version deleted]]
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