1 files changed, 30 insertions, 14 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index cfff7202a3..b5acf211d5 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -16,6 +16,7 @@ module ActiveRecord
     autoload_at 'active_record/connection_adapters/abstract/schema_definitions' do
       autoload :IndexDefinition
       autoload :ColumnDefinition
+      autoload :ChangeColumnDefinition
       autoload :TableDefinition
       autoload :Table
       autoload :AlterTable
@@ -33,12 +34,14 @@ module ActiveRecord
       autoload :Quoting
       autoload :ConnectionPool
       autoload :QueryCache
+      autoload :Savepoints
     end
 
     autoload_at 'active_record/connection_adapters/abstract/transaction' do
       autoload :ClosedTransaction
       autoload :RealTransaction
       autoload :SavepointTransaction
+      autoload :TransactionState
     end
 
     # Active Record supports multiple database systems. AbstractAdapter and
@@ -95,10 +98,9 @@ module ActiveRecord
         @last_use            = false
         @logger              = logger
         @pool                = pool
-        @query_cache         = Hash.new { |h,sql| h[sql] = {} }
-        @query_cache_enabled = false
         @schema_cache        = SchemaCache.new self
         @visitor             = nil
+        @prepared_statements = false
       end
 
       def valid_type?(type)
@@ -210,10 +212,11 @@ module ActiveRecord
       end
 
       def unprepared_statement
-        old, @visitor = @visitor, unprepared_visitor
+        old_prepared_statements, @prepared_statements = @prepared_statements, false
+        old_visitor, @visitor = @visitor, unprepared_visitor
         yield
       ensure
-        @visitor = old
+        @visitor, @prepared_statements = old_visitor, old_prepared_statements
       end
 
       # Returns the human-readable name of the adapter. Use mixed case - one
@@ -293,6 +296,14 @@ module ActiveRecord
         false
       end
 
+      # This is meant to be implemented by the adapters that support extensions
+      def disable_extension(name)
+      end
+
+      # This is meant to be implemented by the adapters that support extensions
+      def enable_extension(name)
+      end
+
       # A list of extensions, to be filled in by adapters that support them. At
       # the moment only postgresql does.
       def extensions
@@ -307,8 +318,8 @@ module ActiveRecord
 
       # QUOTING ==================================================
 
-      # Returns a bind substitution value given a +column+ and list of current
-      # +binds+.
+      # Returns a bind substitution value given a bind +index+ and +column+
+      # NOTE: The column param is currently being used by the sqlserver-adapter
       def substitute_at(column, index)
         Arel::Nodes::BindParam.new '?'
       end
@@ -387,13 +398,13 @@ module ActiveRecord
         @transaction.number
       end
 
-      def create_savepoint
+      def create_savepoint(name = nil)
       end
 
-      def rollback_to_savepoint
+      def rollback_to_savepoint(name = nil)
       end
 
-      def release_savepoint
+      def release_savepoint(name = nil)
       end
 
       def case_sensitive_modifier(node)
@@ -415,13 +426,14 @@ module ActiveRecord
 
       protected
 
-      def log(sql, name = "SQL", binds = [])
+      def log(sql, name = "SQL", binds = [], statement_name = nil)
         @instrumenter.instrument(
           "sql.active_record",
-          :sql           => sql,
-          :name          => name,
-          :connection_id => object_id,
-          :binds         => binds) { yield }
+          :sql            => sql,
+          :name           => name,
+          :connection_id  => object_id,
+          :statement_name => statement_name,
+          :binds          => binds) { yield }
       rescue => e
         message = "#{e.class.name}: #{e.message}: #{sql}"
         @logger.error message if @logger
@@ -434,6 +446,10 @@ module ActiveRecord
         # override in derived class
         ActiveRecord::StatementInvalid.new(message, exception)
       end
+
+      def without_prepared_statement?(binds)
+        !@prepared_statements || binds.empty?
+      end
     end
   end
 end