merge default

2 files changed, 43 insertions, 6 deletions

diff --git a/lib/sqlalchemy/engine/base.py b/lib/sqlalchemy/engine/base.py
index dc42ed957..4c5a6a82b 100644
--- a/lib/sqlalchemy/engine/base.py
+++ b/lib/sqlalchemy/engine/base.py
@@ -794,6 +794,14 @@ class Connection(Connectable):
         """
 
         return self.engine.Connection(self.engine, self.__connection, _branch=True)
+
+    def _clone(self):
+        """Create a shallow copy of this Connection.
+
+        """
+        c = self.__class__.__new__(self.__class__)
+        c.__dict__ = self.__dict__.copy()
+        return c
     
     def execution_options(self, **opt):
         """ Set non-SQL options for the connection which take effect during execution.
@@ -811,9 +819,9 @@ class Connection(Connectable):
         :meth:`sqlalchemy.sql.expression.Executable.execution_options`.
 
         """
-        return self.engine.Connection(
-                    self.engine, self.__connection,
-                     _branch=self.__branch, _execution_options=opt)
+        c = self._clone()
+        c._execution_options = c._execution_options.union(opt)
+        return c
     
     @property
     def dialect(self):
@@ -1142,10 +1150,22 @@ class Connection(Connectable):
         else:
             keys = []
 
+        if 'compiled_cache' in self._execution_options:
+            key = self.dialect, elem, tuple(keys), len(params) > 1
+            if key in self._execution_options['compiled_cache']:
+                compiled_sql = self._execution_options['compiled_cache'][key]
+            else:
+                compiled_sql = elem.compile(
+                                dialect=self.dialect, column_keys=keys, 
+                                inline=len(params) > 1)
+                self._execution_options['compiled_cache'][key] = compiled_sql
+        else:
+            compiled_sql = elem.compile(
+                            dialect=self.dialect, column_keys=keys, 
+                            inline=len(params) > 1)
+
         context = self.__create_execution_context(
-                        compiled_sql=elem.compile(
-                                        dialect=self.dialect, column_keys=keys, 
-                                        inline=len(params) > 1),
+                        compiled_sql=compiled_sql,
                         parameters=params
                     )
         return self.__execute_context(context)
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py
index 5958a0bc4..1222a144f 100644
--- a/lib/sqlalchemy/sql/expression.py
+++ b/lib/sqlalchemy/sql/expression.py
@@ -2276,6 +2276,23 @@ class Executable(_Generative):
           of many DBAPIs.  The flag is currently understood only by the
           psycopg2 dialect.
 
+        * compiled_cache - a dictionary where :class:`Compiled` objects
+          will be cached when the :class:`Connection` compiles a clause 
+          expression into a dialect- and parameter-specific 
+          :class:`Compiled` object.   It is the user's responsibility to
+          manage the size of this dictionary, which will have keys
+          corresponding to the dialect, clause element, the column
+          names within the VALUES or SET clause of an INSERT or UPDATE, 
+          as well as the "batch" mode for an INSERT or UPDATE statement.
+          The format of this dictionary is not guaranteed to stay the
+          same in future releases.
+          
+          This option is usually more appropriate
+          to use via the 
+          :meth:`sqlalchemy.engine.base.Connection.execution_options()`
+          method of :class:`Connection`, rather than upon individual 
+          statement objects, though the effect is the same.
+          
         See also:
         
             :meth:`sqlalchemy.engine.base.Connection.execution_options()`