diff options
| -rw-r--r-- | activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb | 23 |
1 files changed, 23 insertions, 0 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 e3e0839f96..10cae5d840 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb @@ -249,6 +249,29 @@ module ActiveRecord end end + # ConnectionHandler is a collection of ConnectionPool objects. It is used + # for keeping separate connection pools for ActiveRecord models that connect + # to different databases. + # + # For example, suppose that you have 5 models, with the following hierarchy: + # + # | + # +-- Book + # | | + # | +-- ScaryBook + # | +-- GoodBook + # +-- Author + # +-- BankAccount + # + # 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. + # + # Normally there is only a single ConnectionHandler instance, accessible via + # ActiveRecord::Base.connection_handler. ActiveRecord models use this to + # determine that connection pool that they should use. class ConnectionHandler def initialize(pools = {}) @connection_pools = pools |