- Connection has execution_options(), generative method

which accepts keywords that affect how the statement
is executed w.r.t. the DBAPI.   Currently supports
"stream_results", causes psycopg2 to use a server
side cursor for that statement.   Can also be set
upon select() and text() constructs directly as well
as ORM Query().

2 files changed, 10 insertions, 9 deletions

diff --git a/lib/sqlalchemy/engine/base.py b/lib/sqlalchemy/engine/base.py
index e74e00d84..3d192a9be 100644
--- a/lib/sqlalchemy/engine/base.py
+++ b/lib/sqlalchemy/engine/base.py
@@ -719,10 +719,10 @@ class Connection(Connectable):
     .. index::
       single: thread safety; Connection
     """
-    options = {}
+    _execution_options = util.frozendict()
     
     def __init__(self, engine, connection=None, close_with_result=False,
-                 _branch=False, _options=None):
+                 _branch=False, _execution_options=None):
         """Construct a new Connection.
 
         Connection objects are typically constructed by an
@@ -736,8 +736,8 @@ class Connection(Connectable):
         self.__savepoint_seq = 0
         self.__branch = _branch
         self.__invalid = False
-        if _options:
-            self.options = _options
+        if _execution_options:
+            self._execution_options = self._execution_options.union(_execution_options)
 
     def _branch(self):
         """Return a new Connection which references this Connection's
@@ -750,7 +750,7 @@ class Connection(Connectable):
 
         return self.engine.Connection(self.engine, self.__connection, _branch=True)
     
-    def _with_options(self, **opt):
+    def execution_options(self, **opt):
         """Add keyword options to a Connection generatively.
         
         Experimental.  May change the name/signature at 
@@ -763,7 +763,7 @@ class Connection(Connectable):
         """
         return self.engine.Connection(
                     self.engine, self.__connection,
-                     _branch=self.__branch, _options=opt)
+                     _branch=self.__branch, _execution_options=opt)
     
     @property
     def dialect(self):
diff --git a/lib/sqlalchemy/engine/default.py b/lib/sqlalchemy/engine/default.py
index bb3688597..6db655832 100644
--- a/lib/sqlalchemy/engine/default.py
+++ b/lib/sqlalchemy/engine/default.py
@@ -224,13 +224,13 @@ class DefaultDialect(base.Dialect):
 
 
 class DefaultExecutionContext(base.ExecutionContext):
-    execution_options = util.frozendict()
     
     def __init__(self, dialect, connection, compiled_sql=None, compiled_ddl=None, statement=None, parameters=None):
         self.dialect = dialect
         self._connection = self.root_connection = connection
         self.engine = connection.engine
-
+        self.execution_options = connection._execution_options
+        
         if compiled_ddl is not None:
             self.compiled = compiled = compiled_ddl
             if not dialect.supports_unicode_statements:
@@ -268,7 +268,8 @@ class DefaultExecutionContext(base.ExecutionContext):
             self.isinsert = compiled.isinsert
             self.isupdate = compiled.isupdate
             self.isdelete = compiled.isdelete
-            self.execution_options = compiled.statement._execution_options
+            self.execution_options =\
+                    compiled.statement._execution_options.union(self.execution_options)
 
             if not parameters:
                 self.compiled_parameters = [compiled.construct_params()]