diff options
Diffstat (limited to 'activerecord/lib/active_record/connection_adapters')
-rw-r--r-- | activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb | 51 |
1 files changed, 36 insertions, 15 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb index cb75070e3a..a5fa9d6adc 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb @@ -462,23 +462,44 @@ module ActiveRecord # # For example, suppose that you have 5 models, with the following hierarchy: # - # | - # +-- Book - # | | - # | +-- ScaryBook - # | +-- GoodBook - # +-- Author - # +-- BankAccount + # class Author < ActiveRecord::Base + # end # - # Suppose that Book is to connect to a separate database (i.e. one other - # than the default database). Then Book, ScaryBook and GoodBook will all use - # the same connection pool. Likewise, Author and BankAccount will use the - # same connection pool. However, the connection pool used by Author/BankAccount - # is not the same as the one used by Book/ScaryBook/GoodBook. + # class BankAccount < ActiveRecord::Base + # end # - # Normally there is only a single ConnectionHandler instance, accessible via - # ActiveRecord::Base.connection_handler. Active Record models use this to - # determine the connection pool that they should use. + # class Book < ActiveRecord::Base + # establish_connection "library_db" + # end + # + # class ScaryBook < Book + # end + # + # class GoodBook < Book + # end + # + # And a database.yml that looked like this: + # + # development: + # database: my_application + # host: localhost + # + # library_db: + # database: library + # host: some.library.org + # + # Your primary database in the development environment is "my_application" + # but the Book model connects to a separate database called "library_db" + # (this can even be a database on a different machine). + # + # Book, ScaryBook and GoodBook will all use the same connection pool to + # "library_db" while Author, BankAccount, and any other models you create + # will use the default connection pool to "my_application". + # + # The various connection pools are managed by a single instance of + # ConnectionHandler accessible via ActiveRecord::Base.connection_handler. + # All Active Record models use this handler to determine the connection pool that they + # should use. class ConnectionHandler def initialize # These caches are keyed by klass.name, NOT klass. Keying them by klass |