From: Robert Dober <robert.dober@...>
Date: 2007-02-23T03:17:32+09:00
Subject: Re: Numerical calculation returns string with DBI/Mysql

On 2/22/07, Ken Bloom <kbloom@gmail.com> wrote:
> When I run the following query in DBI/Mysql, I'm finding that DBI is
> returning the rho column as a string (rather than a float), thus forcing me
> to convert it to a float with to_f. (I lose precision because the string
> only returns the result to three decimal places). Any idea why DBI/Mysql is
> returning the result of a numerical calculation as a string?
>
> I'm running
> mysql-5.0.34_alpha20070101-r61
> mysql-ruby-2.7.2
> ruby-dbi-0.0.21-r2
> ruby-1.8.5_p2
> on Gentoo.
>
> dbh.execute("select childcounts.name name, childcounts.count/
> parentcounts.count rho from parentcounts, childcounts where
> parentcounts.left_key=childcounts.parent_left")
>
Hi Ken
if this is an issue it is a MySQL issue I guess, concerning ruby, do
you have a compelling reason not to write

dbh.execute("select childcounts.name name, childcounts.count whatever,
parentcounts.count rho from parentcounts, childcounts where
 parentcounts.left_key=childcounts.parent_left")

and let the gem do the arithmetic? (performance maybe)

Cheers
Robert
> --
> Ken Bloom. PhD candidate. Linguistic Cognition Laboratory.
> Department of Computer Science. Illinois Institute of Technology.
> http://www.iit.edu/~kbloom1/
>
>


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