Multiple database connections

Question

I'm trying to figure out how best to get a connection to my databases.

Right now I have a method that parses the URL (depending on the URL that the application should connect to another database, for example client1.example.com will connect to customer1 database) and calls

ActiveRecord::Base.establish_connection(conn_string)

where conn_string contains the database name.

This method (set_db) is called using

before_filter :set_db

in my application controller, so basically for every request I receive, the URL is parsed and the application is trying to set connection_connection.

I was wondering if I have a connection pool somewhere ... do you have any suggestions on this? Is it better to have a singleton that supports all connections and returns the correct one?

Thanks! Roberto

Answer 1

Are databases on a single server?

I have an application in which some of the model objects from one database and others from another database. I override the table_name function to indicate the database. It does not work if they are different servers, but will work for different databases on the same server.

class xx < ActiveRecord.base

def self.table_name
  "otherdatabase.table"
end

It looks like the database pool might be on the way for an advanced version of rails.

What's New in Edge Rails

Answer 2

I'm not a Ruby programmer, but generally speaking, a connection pool is a good idea. You can make this connection pool a single and transfer / return connections. The pool can check after the connection returns that everything is all right.

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Answer 3

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Answer 4

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RewriteCond %{HTTP_HOST} ^(.*)$
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RequestHeader set Customer-Key %{ACCOUNT}e

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I am sure that you have addressed migration issues. This was not a problem in the beginning with <2000. Now there are> 15 thousand Client databases (and growing), so we combine them back into a small number of plastered databases.