# Run query on IRB

**URL:** <https://www.ruby-forum.com/t/run-query-on-irb/188032>\
**Category:** Rails\
**Created:** [May 4, 2010, 3:36pm UTC](https://www.ruby-forum.com/t/run-query-on-irb/188032 "2010-05-04T15:36:21Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![jv\_neto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/ecccb3/32.png) [@jv\_neto](https://www.ruby-forum.com/u/jv_neto)\
**Post date:** [May 4, 2010, 3:36pm UTC](https://www.ruby-forum.com/t/run-query-on-irb/188032/1 "2010-05-04T15:36:21Z")

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Hi All  
I never worked with RUBY my fisrt time.

I’d like to run this query by IRB and see how many line it will show  
me :

select codigo, nome from teste

My database is postgre 8.4

Look what i did to do it:

irb(main):006:0\> Post.find\_by\_sql “SELECT codigo, tirulo from teste”  
NameError: uninitialized constant Post  
from (irb):6  
irb(main):007:0\>

What is going on there?

Thanks

Grato

---

<div class="post-metadata">

**Author:** ![jv\_neto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/ecccb3/32.png) [@jv\_neto](https://www.ruby-forum.com/u/jv_neto)\
**Post date:** [May 4, 2010, 7:02pm UTC](https://www.ruby-forum.com/t/run-query-on-irb/188032/2 "2010-05-04T19:02:27Z")

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Yes and it created tha database.yml

development:  
adapter: postgresql  
encoding: unicode  
database: postgres\_development  
pool: 5  
username: postgres  
password: 031969

test:  
adapter: postgresql  
encoding: unicode  
database: rubyPostgre\_test  
pool: 5  
username: rubyPostgre  
password:

production:  
adapter: postgresql  
encoding: unicode  
database: rubyPostgre\_production  
pool: 5  
username: rubyPostgre  
password:

And my query it to be runing on development enviroment.  
Can u help me run my query?

Thanks

2010/5/4 Dhruva S. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

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<div class="post-metadata">

**Author:** ![jv\_neto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/ecccb3/32.png) [@jv\_neto](https://www.ruby-forum.com/u/jv_neto)\
**Post date:** [May 4, 2010, 3:43pm UTC](https://www.ruby-forum.com/t/run-query-on-irb/188032/3 "2010-05-04T15:43:22Z")

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Have you created a rails application ?  
What in your opinion is Post? Ruby expects to find a constant by that  
name.  
class names in Ruby are constants. constant is any word that starts with  
a  
capital letter.

If say you’ve written a class Post, then you must have done so in a  
file.  
You need to require that file when inside irb to load that class.

On Tue, May 4, 2010 at 17:08, jv neto [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> Look what i did to do it:
> 
> [http://groups.google.com/group/rubyonrails-talk?hl=en](http://groups.google.com/group/rubyonrails-talk?hl=en).

–

Thanks & Regards,  
Dhruva S…

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<div class="post-metadata">

**Author:** ![jv\_neto](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/ecccb3/32.png) [@jv\_neto](https://www.ruby-forum.com/u/jv_neto)\
**Post date:** [May 5, 2010, 2:15am UTC](https://www.ruby-forum.com/t/run-query-on-irb/188032/4 "2010-05-05T02:15:35Z")

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Hi, if it’s rails.  
You should go to your applications root & type ‘ruby script/console’ ,  
if  
your on a mac you could just type ‘script/console’.

When the console starts, you will be able to do what you were trying to  
do  
in your IRB.

On Tue, May 4, 2010 at 22:30, jv neto [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> test:  
> database: rubyPostgre\_production
> 
> > On Tue, May 4, 2010 at 17:08, jv neto [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:
> > 
> > > Thanks  
> > > For more options, visit this group at  
> > > –  
> > > –  
> > > You received this message because you are subscribed to the Google G.  
> > > “Ruby on Rails: Talk” group.  
> > > To post to this group, send email to removed\_email\_address@domain.invalid.  
> > > To unsubscribe from this group, send email to  
> > > removed\_email\_address@domain.invalid[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
> > > .  
> > > For more options, visit this group at  
> > > [http://groups.google.com/group/rubyonrails-talk?hl=en](http://groups.google.com/group/rubyonrails-talk?hl=en).

–

Thanks & Regards,  
Dhruva S…