Creating databases on the fly

rubyonrails-talk
1

Hi,

Is there a recommended way of creating a new database from within rails? (or is the recommended way not to do it?)

In my application I wish to be able to create a new database structure for each user who signs up, but there doesn't seem to be a way of doing this using ActiveRecord.

At present I can create it by establishing a new connection to the database dbh = Mysql.real_connect(...) then doing something like this dbh.query("create database " + database_name) which works fine with my windows machine (with mysql-win gem installed) but not my linux server.

Any advice is greatly appreciated. Many thanks Tim

2

Migrations, maybe? Search for that on the rails wiki.

3

Tim,

You can use the ActiveRecord connection adapters, something like:

ActiveRecord::Base.connection.execute("CREATE DATABASE #{db_name}")

However you better be very sure to sanitize that incoming data. The statement above on its own is ripe for SQL injection.

V/r Anthony Eden

4

In my application I wish to be able to create a new database structure for each user who signs up, but there doesn't seem to be a way of doing this using ActiveRecord.

Are you absolutely sure that's what you want? Usually this leads to all kinds of horrible problems. If you just want to support multiple, separate accounts in your application, you do not want to use separate databases. Instead, just have your content tables reference an account table and use the object hierarchy to protect against data bleeding.

class Account < ActiveRecord::Base   has_many :people end

class Person < ActiveRecord::Base   belongs_to :account end

Then you find some way of identifying which account someone is using (like a subdomain in the URL is common) and load that into @account. Now you can do @account.people.find(params[:id]) and rest assured that nobody will be able to access people from outside of their own account.