Deduplicate various Active Record schema cache structures

Real world database schemas contain a lot of duplicated data.
Some column names like `id`, `created_at` etc can easily be repeated
hundreds of times. Same for SqlTypeMetada, most database will contain
only a limited number of possible combinations.

This result in a lot of wasted memory.

The idea here is to make these data sctructures immutable, use a registry
to substitute similar instances with pre-existing ones.

1 files changed, 9 insertions, 9 deletions

diff --git a/activerecord/test/models/contact.rb b/activerecord/test/models/contact.rb
index 6e02ff199b..d5f6f00691 100644
--- a/activerecord/test/models/contact.rb
+++ b/activerecord/test/models/contact.rb
@@ -10,14 +10,14 @@ module ContactFakeColumns
         table_name => "id"
       }
 
-      column :id,             :integer
-      column :name,           :string
-      column :age,            :integer
-      column :avatar,         :binary
-      column :created_at,     :datetime
-      column :awesome,        :boolean
-      column :preferences,    :string
-      column :alternative_id, :integer
+      column :id,             "integer"
+      column :name,           "string"
+      column :age,            "integer"
+      column :avatar,         "binary"
+      column :created_at,     "datetime"
+      column :awesome,        "boolean"
+      column :preferences,    "string"
+      column :alternative_id, "integer"
 
       serialize :preferences
 
@@ -37,7 +37,7 @@ end
 
 class ContactSti < ActiveRecord::Base
   extend ContactFakeColumns
-  column :type, :string
+  column :type, "string"
 
   def type; "ContactSti" end
 end