# Dbi

**URL:** <https://www.ruby-forum.com/t/dbi/159795>\
**Category:** Ruby\
**Created:** [February 8, 2009, 10:46pm UTC](https://www.ruby-forum.com/t/dbi/159795 "2009-02-08T22:46:57Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![henriklarsen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/e9bcb4/32.png) [@henriklarsen](https://www.ruby-forum.com/u/henriklarsen)\
**Post date:** [February 8, 2009, 10:46pm UTC](https://www.ruby-forum.com/t/dbi/159795/1 "2009-02-08T22:46:57Z")

</div>

Hi everyone,

I have a problem connecting my application to a database. I think this  
is a ruby problem though Im running ruby on rails, but let me explain.  
The thing is that I want to execute queries upon several different  
databases by using DBI/DBD and not activerecord. For this I have created  
a simple ruby class with the responsibility of fetching different data.  
This class looks something like the this:

require ‘dbi’  
class DataAccess

def self.methodA  
begin  
# connect to the MySQL server  
dbh = DBI.connect(“DBI:mysql:localhost”, “username”, “password”)  
# get server version string and display it  
row = dbh.select\_one(“SELECT …”)  
rescue DBI::DatabaseError =\> error  
puts “An error occurred”  
ensure  
# disconnect from server  
dbh.disconnect if dbh  
end

def self.methodB  
#same as above, different database  
…  
end

end

When these methods are executed i get the following error:  
Could not load driver (undefined local variable or method `e’ for  
DBI:Module)  
…

Anyone have a sollution for this? I have tried following every guide  
there is to connect ruby to a database (installation of dbi/dbd). Maybe  
someone could explain what im doing wrong?

---

<div class="post-metadata">

**Author:** ![henriklarsen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/h/e9bcb4/32.png) [@henriklarsen](https://www.ruby-forum.com/u/henriklarsen)\
**Post date:** [February 9, 2009, 12:26pm UTC](https://www.ruby-forum.com/t/dbi/159795/2 "2009-02-09T12:26:37Z")

</div>

Henrik Larsen wrote:

> When these methods are executed i get the following error:  
> Could not load driver (undefined local variable or method `e’ for  
> DBI:Module)  
> …

(1) Try it from the command line, using irb - firstly using native DBI  
commands, and then using your wrapper class. Only when it’s working  
there think about porting it into Rails.

(2) If you can’t get it to work, make the smallest standalone code you  
can which reproduces the problem.

(3) Post this standalone code, and post the _full_ unedited backtrace  
you get when running it. The above error message isn’t much use, as it  
didn’t say whether the error was in the DBI code itself, or your code.

Finally, beware that DBI has changed quite a bit between 0.2 and 0.4, so  
if you are reading random pages on the web, beware that they may be out  
of date.

HTH,

Brian.