From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Sun, 29 Jun 2014 04:10:59 +0000 (-0400)
Subject: - attach the ResultMetaData to the Compiled object, when we detect that
X-Git-Tag: rel_1_0_0b1~367
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=992e06412cf124d511d56d2741988f503f4c8085;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

- 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.
---

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.