[ticket:280] statement execution supports using the same BindParam

object more than once in an expression; simplified handling of positional
parameters.  nice job by Bill Noon figuring out the basic idea.

1 files changed, 12 insertions, 5 deletions

diff --git a/lib/sqlalchemy/sql.py b/lib/sqlalchemy/sql.py
index 18591c24c..2aa1342ca 100644
--- a/lib/sqlalchemy/sql.py
+++ b/lib/sqlalchemy/sql.py
@@ -273,12 +273,19 @@ class AbstractDialect(object):
     """represents the behavior of a particular database.  Used by Compiled objects."""
     pass
     
-class ClauseParameters(util.OrderedDict):
-    """represents a dictionary/iterator of bind parameter key names/values.  Includes parameters compiled with a Compiled object as well as additional arguments passed to the Compiled object's get_params() method.  Parameter values will be converted as per the TypeEngine objects present in the bind parameter objects.  The non-converted value can be retrieved via the get_original method.  For Compiled objects that compile positional parameters, the values() iteration of the object will return the parameter values in the correct order."""
-    def __init__(self, dialect):
+class ClauseParameters(dict):
+    """represents a dictionary/iterator of bind parameter key names/values.  
+    
+    Tracks the original BindParam objects as well as the keys/position of each
+    parameter, and can return parameters as a dictionary or a list.
+    Will process parameter values according to the TypeEngine objects present in
+    the BindParams.
+    """
+    def __init__(self, dialect, positional=None):
         super(ClauseParameters, self).__init__(self)
         self.dialect=dialect
         self.binds = {}
+        self.positional = positional or []
     def set_parameter(self, key, value, bindparam):
         self[key] = value
         self.binds[key] = bindparam
@@ -290,10 +297,10 @@ class ClauseParameters(util.OrderedDict):
         if self.binds.has_key(key):
             v = self.binds[key].typeprocess(v, self.dialect)
         return v
-    def values(self):
-        return [self[key] for key in self]
     def get_original_dict(self):
         return self.copy()
+    def get_raw_list(self):
+        return [self[key] for key in self.positional]
     def get_raw_dict(self):
         d = {}
         for k in self: