# Create databases on demand **URL:** \ **Category:** Rails\ **Created:** [November 13, 2007, 3:59pm UTC](https://www.ruby-forum.com/t/create-databases-on-demand/120075 "2007-11-13T15:59:06Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![sp00nyg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/edb3f5/32.png) [@sp00nyg](https://www.ruby-forum.com/u/sp00nyg)\ **Post date:** [November 13, 2007, 3:59pm UTC](https://www.ruby-forum.com/t/create-databases-on-demand/120075/1 "2007-11-13T15:59:06Z")
Sorry if this has been asked before: I am developing a month-to-month service similar to > **[Project management software, online collaboration](https://basecamp.com/)** > > Trusted by millions, Basecamp puts everything you need to get work done in one place. It’s the calm, organized way to manage projects, work with clients, and communicate company-wide. and planning to operate it on a hosting site. I plan to simply deploy a copy of my application for each customer with their own database instance. It doesn’t appear as if my provider allows dynamic creation of databases, which leads to my question: Does it even make sense to create a production database for each customer or should I modify my models so that customers share the tables. This would be a lot of work (24 models) - it would certainly be much DRYer though. I can imagine it would be a nightmare updating table elements on 100s of databases… What do you think? Should I look for a provider that will give me root access to MySQL or bite the bullet and do the work now? Thanks in advance. -Dave ---
**Author:** ![sp00nyg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/edb3f5/32.png) [@sp00nyg](https://www.ruby-forum.com/u/sp00nyg)\ **Post date:** [November 13, 2007, 10:26pm UTC](https://www.ruby-forum.com/t/create-databases-on-demand/120075/2 "2007-11-13T22:26:43Z")
> This would be a lot of work (24 models) - it would certainly > be much DRYer though. I can imagine it would be a nightmare > updating table elements on 100s of databases… > > What do you think? Should I look for a provider that will > give me root access to MySQL or bite the bullet and do the work now? I always try to include a root object in my schemas to which everything belongs, either directly or, more often, indirectly via its ancestors. That tends to make it easy to scale horizontally by adding new root objects. I would suggest that’s probably easier than maintaining N instances of your database. The only real downside is that when you upgrade your schema, all of your customers have to upgrade at once, but that’s probably a feature rather than a bug for a hosted service like you describe. - donald ---
**Author:** ![sp00nyg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/edb3f5/32.png) [@sp00nyg](https://www.ruby-forum.com/u/sp00nyg)\ **Post date:** [November 14, 2007, 4:56pm UTC](https://www.ruby-forum.com/t/create-databases-on-demand/120075/3 "2007-11-14T16:56:50Z")
Thanks for your reply, Donald. So then it might make sense to introduce an Account object to own all my other objects. I’m just thinking about the task list to implement: - migration to handle creating Account and adding the foreign keys to all the other tables. - Account Model with has\_many relationships - add belongs\_to account relationships to existing models - introduce find\_by\_account clause to each controller that creates an instance of the system models. - other items… So how would this work in practice with creating accounts and users? For example I’m creating a CRM system where a user can manage customer contacts and I want to log Fred in so he can manage his customers: accounts has\_many users, customers user belongs\_to account customer belongs\_to account users has\_many customers customer belongs\_to user I’ll have to give this some more thought. How have you tackled this? Regards, Dave On Nov 13, 1:16 pm, “Ball, Donald A Jr (Library)” ---
**Author:** ![sp00nyg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/edb3f5/32.png) [@sp00nyg](https://www.ruby-forum.com/u/sp00nyg)\ **Post date:** [November 14, 2007, 5:25pm UTC](https://www.ruby-forum.com/t/create-databases-on-demand/120075/4 "2007-11-14T17:25:31Z")
On 14 Nov, 15:55, Dave [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I’ll have to give this some more thought. How have you tackled this? Hi Dave, I’m creating something similar at the moment - not a CRM, I hasten to add. In my application, an account has many users and has many contracts. Any user can amend a contract belonging to that user’s account. On that basis, it is very similar to the schema you have outlined above. By having a customer belonging to a user, it should be easy enough to restrict editing the customer’s details to that one user. I’m using the Account Location plugin on my app so that I can use urls such as [accountname.myapp.com](http://accountname.myapp.com) pretty much in the same vain as Basecamp. Best Regards Robin ---
**Author:** ![sp00nyg](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/edb3f5/32.png) [@sp00nyg](https://www.ruby-forum.com/u/sp00nyg)\ **Post date:** [November 15, 2007, 5:16am UTC](https://www.ruby-forum.com/t/create-databases-on-demand/120075/5 "2007-11-15T05:16:38Z")
Excellent tip, Robin! I hadn’t heard of the Account Location plugin. It sounds like just the thing I need. Thanks and good luck with your application! This book was recommended to me today and it looks very good, so I’ll pass the link on to you. Thanks again! > **[Getting Real](https://basecamp.com/gettingreal)** > > The smarter, faster, easier way to build a successful web application Dave