# Rails 3 DataMapper dm-rails sqlite3 issue

**URL:** <https://www.ruby-forum.com/t/rails-3-datamapper-dm-rails-sqlite3-issue/195989>\
**Category:** Rails\
**Created:** [October 4, 2010, 11:23pm UTC](https://www.ruby-forum.com/t/rails-3-datamapper-dm-rails-sqlite3-issue/195989 "2010-10-04T23:23:29Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![juan](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/a698b9/32.png) [@juan](https://www.ruby-forum.com/u/juan)\
**Post date:** [October 4, 2010, 11:23pm UTC](https://www.ruby-forum.com/t/rails-3-datamapper-dm-rails-sqlite3-issue/195989/1 "2010-10-04T23:23:29Z")

</div>

I’ve tried to take a look to DataMapper with Rails 3, so I follow this  
simple instruction on [GitHub - datamapper/dm-rails: Integrate DataMapper with Rails 3](http://github.com/datamapper/dm-rails).

$ rails new testing\_dm3 -m [http://datamapper.org/templates/rails.rb](http://datamapper.org/templates/rails.rb)  
$ cd testing\_dm3  
$ bundle install  
$ rails g scaffold Person name:string  
$ rake db:setup  
/Users/jm/.rvm/gems/ruby-head@rails3dm/gems/rake-0.8.7/lib/rake/alt\_system.rb:32:  
Use RbConfig instead of obsolete and deprecated Config.  
(in /Users/jm/dev/personal/testing\_dm3)  
[datamapper] Created database ‘testing\_dm3\_development.db’  
[datamapper] Created database ‘testing\_dm3\_test.db’  
[datamapper] Finished auto\_migrate! for :default repository  
‘testing\_dm3\_development.db’

$ thin start (I like thin)

Go to [http://0.0.0.0:3000/people](http://0.0.0.0:3000/people) and you should see

DataObjects::SyntaxError in People#index  
no such table: people

If you don’t, you are lucky. I fixed this modifying database.yml:

change “database” to “path”  
database: testing\_dm3\_development.db  
to  
path: ./db/testing\_dm3\_development.db

and run:

$ rake db:setup (again)

That fixed it for me. That happend because the database is in\_memory and  
doesn’t create the files, if you run the migration on a rails console,  
inside the console you can CRUD your objects, but when you left the  
session you lost the data.