1 files changed, 23 insertions, 16 deletions
diff --git a/lib/sqlalchemy/ansisql.py b/lib/sqlalchemy/ansisql.py
index f96bf7abe..19cde3862 100644
--- a/lib/sqlalchemy/ansisql.py
+++ b/lib/sqlalchemy/ansisql.py
@@ -10,7 +10,7 @@ Contains default implementations for the abstract objects in the sql
 module.
 """
 
-from sqlalchemy import schema, sql, engine, util, sql_util
+from sqlalchemy import schema, sql, engine, util, sql_util, exceptions
 from  sqlalchemy.engine import default
 import string, re, sets, weakref
 
@@ -353,20 +353,27 @@ class ANSICompiler(sql.Compiled):
     def visit_bindparam(self, bindparam):
         if bindparam.shortname != bindparam.key:
             self.binds.setdefault(bindparam.shortname, bindparam)
-        count = 1
-        key = bindparam.key
-
-        # redefine the generated name of the bind param in the case
-        # that we have multiple conflicting bind parameters.
-        while self.binds.setdefault(key, bindparam) is not bindparam:
-            # ensure the name doesn't expand the length of the string
-            # in case we're at the edge of max identifier length
-            tag = "_%d" % count
-            key = bindparam.key[0 : len(bindparam.key) - len(tag)] + tag
-            count += 1
-        bindparam.key = key
-        self.strings[bindparam] = self.bindparam_string(key)
-
+        if bindparam.unique:
+            count = 1
+            key = bindparam.key
+
+            # redefine the generated name of the bind param in the case
+            # that we have multiple conflicting bind parameters.
+            while self.binds.setdefault(key, bindparam) is not bindparam:
+                # ensure the name doesn't expand the length of the string
+                # in case we're at the edge of max identifier length
+                tag = "_%d" % count
+                key = bindparam.key[0 : len(bindparam.key) - len(tag)] + tag
+                count += 1
+            bindparam.key = key
+            self.strings[bindparam] = self.bindparam_string(key)
+        else:
+            existing = self.binds.get(bindparam.key)
+            if existing is not None and existing.unique:
+                raise exceptions.CompileError("Bind parameter '%s' conflicts with unique bind parameter of the same name" % bindparam.key)
+            self.strings[bindparam] = self.bindparam_string(bindparam.key)
+            self.binds[bindparam.key] = bindparam
+            
     def bindparam_string(self, name):
         return self.bindtemplate % name
 
@@ -702,7 +709,7 @@ class ANSICompiler(sql.Compiled):
             if parameters.has_key(c):
                 value = parameters[c]
                 if sql._is_literal(value):
-                    value = sql.bindparam(c.key, value, type=c.type)
+                    value = sql.bindparam(c.key, value, type=c.type, unique=True)
                 values.append((c, value))
         return values