added explicit bind parameters and column type maps to text type

text type also parses :<string> into bind param objects
bind parameters convert their incoming type using engine.type_descriptor() methods
types.adapt_type() adjusted to not do extra work with incoming types, since the bind
param change will cause it to be called a lot more
added tests to new text type stuff, bind params, fixed some type tests
added basic docs for using text with binde params

1 files changed, 4 insertions, 0 deletions

diff --git a/lib/sqlalchemy/engine.py b/lib/sqlalchemy/engine.py
index 054c5853c..a1e57f6b3 100644
--- a/lib/sqlalchemy/engine.py
+++ b/lib/sqlalchemy/engine.py
@@ -223,6 +223,10 @@ class SQLEngine(schema.SchemaEngine):
         if type(typeobj) is type:
             typeobj = typeobj()
         return typeobj
+
+    def text(self, text, *args, **kwargs):
+        """returns a sql.text() object for performing literal queries."""
+        return sql.text(text, engine=self, *args, **kwargs)
         
     def schemagenerator(self, proxy, **params):
         """returns a schema.SchemaVisitor instance that can generate schemas, when it is