cache column defaults for AR object instantiation

1 files changed, 9 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 090f6bc6fe..ddfdb05297 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -60,6 +60,7 @@ module ActiveRecord
       attr_accessor :automatic_reconnect
       attr_reader :spec, :connections
       attr_reader :columns, :columns_hash, :primary_keys, :tables
+      attr_reader :column_defaults
 
       # Creates a new ConnectionPool object. +spec+ is a ConnectionSpecification
       # object which describes database connection information (e.g. adapter,
@@ -106,6 +107,12 @@ module ActiveRecord
           }]
         end
 
+        @column_defaults = Hash.new do |h, table_name|
+          h[table_name] = Hash[columns[table_name].map { |col|
+            [col.name, col.default]
+          }]
+        end
+
         @primary_keys = Hash.new do |h, table_name|
           h[table_name] = with_connection do |conn|
             table_exists?(table_name) ? conn.primary_key(table_name) : 'id'
@@ -133,6 +140,7 @@ module ActiveRecord
       def clear_cache!
         @columns.clear
         @columns_hash.clear
+        @column_defaults.clear
         @tables.clear
       end
 
@@ -140,6 +148,7 @@ module ActiveRecord
       def clear_table_cache!(table_name)
         @columns.delete table_name
         @columns_hash.delete table_name
+        @column_defaults.delete table_name
         @primary_keys.delete table_name
       end