1 files changed, 73 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
new file mode 100644
index 0000000000..1e8dd045f6
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -0,0 +1,73 @@
+module ActiveRecord
+  module ConnectionAdapters # :nodoc:
+    # TODO: Document me!
+    module DatabaseStatements
+      # Returns an array of record hashes with the column names as a keys and fields as values.
+      def select_all(sql, name = nil) end
+
+      # Returns a record hash with the column names as a keys and fields as values.
+      def select_one(sql, name = nil) end
+
+      # Returns a single value from a record
+      def select_value(sql, name = nil)
+        result = select_one(sql, name)
+        result.nil? ? nil : result.values.first
+      end
+
+      # Returns an array of the values of the first column in a select:
+      #   select_values("SELECT id FROM companies LIMIT 3") => [1,2,3]
+      def select_values(sql, name = nil)
+        result = select_all(sql, name)
+        result.map{ |v| v.values.first }
+      end
+
+      # Executes the statement
+      def execute(sql, name = nil) end
+
+      # Returns the last auto-generated ID from the affected table.
+      def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) end
+
+      # Executes the update statement and returns the number of rows affected.
+      def update(sql, name = nil) end
+
+      # Executes the delete statement and returns the number of rows affected.
+      def delete(sql, name = nil) end
+
+      # Wrap a block in a transaction.  Returns result of block.
+      def transaction(start_db_transaction = true)
+        begin
+          if block_given?
+            begin_db_transaction if start_db_transaction
+            result = yield
+            commit_db_transaction if start_db_transaction
+            result
+          end
+        rescue Exception => database_transaction_rollback
+          rollback_db_transaction if start_db_transaction
+          raise
+        end
+      end
+
+      # Begins the transaction (and turns off auto-committing).
+      def begin_db_transaction()    end
+
+      # Commits the transaction (and turns on auto-committing).
+      def commit_db_transaction()   end
+
+      # Rolls back the transaction (and turns on auto-committing). Must be done if the transaction block
+      # raises an exception or returns false.
+      def rollback_db_transaction() end
+
+      def add_limit!(sql, options) #:nodoc:
+        return unless options
+        add_limit_offset!(sql, options)
+      end
+
+      def add_limit_offset!(sql, options) #:nodoc:
+        return if options[:limit].nil?
+        sql << " LIMIT #{options[:limit]}"
+        sql << " OFFSET #{options[:offset]}" if options.has_key?(:offset) and !options[:offset].nil?
+      end
+    end
+  end
+end
+\ No newline at end of file