From 992e06412cf124d511d56d2741988f503f4c8085 Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Sun, 29 Jun 2014 00:10:59 -0400
Subject: [PATCH] - attach the ResultMetaData to the Compiled object, when we
 detect that the compiled cache is used.  That allows us to cache the whole
 metadata and save on creating it at result time, when compiled cache is used.

---
 lib/sqlalchemy/engine/result.py | 16 ++++++++++++----
 lib/sqlalchemy/sql/compiler.py  |  2 ++
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/lib/sqlalchemy/engine/result.py b/lib/sqlalchemy/engine/result.py
index 6c98dae186..0838d810da 100644
--- a/lib/sqlalchemy/engine/result.py
+++ b/lib/sqlalchemy/engine/result.py
@@ -269,9 +269,6 @@ class ResultMetaData(object):
         # high precedence keymap.
         keymap.update(primary_keymap)
 
-        if parent._echo:
-            context.engine.logger.debug(
-                "Col %r", tuple(x[0] for x in metadata))
 
     @util.pending_deprecation("0.8", "sqlite dialect uses "
                     "_translate_colname() now")
@@ -406,7 +403,18 @@ class ResultProxy(object):
     def _init_metadata(self):
         metadata = self._cursor_description()
         if metadata is not None:
-            self._metadata = ResultMetaData(self, metadata)
+            if self.context.compiled and \
+                    'compiled_cache' in self.context.execution_options:
+                if self.context.compiled._cached_metadata:
+                    self._metadata = self.context.compiled._cached_metadata
+                else:
+                    self._metadata = self.context.compiled._cached_metadata = \
+                        ResultMetaData(self, metadata)
+            else:
+                self._metadata = ResultMetaData(self, metadata)
+            if self._echo:
+                    self.context.engine.logger.debug(
+                    "Col %r", tuple(x[0] for x in metadata))
 
     def keys(self):
         """Return the current set of string keys for rows."""
diff --git a/lib/sqlalchemy/sql/compiler.py b/lib/sqlalchemy/sql/compiler.py
index 11608ef3b9..010df5a160 100644
--- a/lib/sqlalchemy/sql/compiler.py
+++ b/lib/sqlalchemy/sql/compiler.py
@@ -170,6 +170,8 @@ class Compiled(object):
     defaults.
     """
 
+    _cached_metadata = None
+
     def __init__(self, dialect, statement, bind=None,
                 compile_kwargs=util.immutabledict()):
         """Construct a new ``Compiled`` object.
-- 
2.47.3