- fix mssql compiling explicitly added alias twice

- add is_select to mssql dialect. currently adds only sp_columns, someone familiar with mssql should update this
- update mssql get_default_schema_name api
- remove commented code from Query.filter_by

2 files changed, 12 insertions, 9 deletions

diff --git a/lib/sqlalchemy/databases/mssql.py b/lib/sqlalchemy/databases/mssql.py
index 5faaf31bf..77819cc92 100644
--- a/lib/sqlalchemy/databases/mssql.py
+++ b/lib/sqlalchemy/databases/mssql.py
@@ -39,7 +39,7 @@ Known issues / TODO:
   
 """
 
-import datetime, random, warnings
+import datetime, random, warnings, re
 
 from sqlalchemy import sql, schema, ansisql, exceptions
 import sqlalchemy.types as sqltypes
@@ -294,6 +294,12 @@ class MSSQLExecutionContext(default.DefaultExecutionContext):
                     # print "LAST ROW ID", self._last_inserted_ids
             self.HASIDENT = False
         super(MSSQLExecutionContext, self).post_exec()
+    
+    _ms_is_select = re.compile(r'\s*(?:SELECT|sp_columns)',
+                               re.I | re.UNICODE)
+    
+    def is_select(self):
+        return self._ms_is_select.match(self.statement) is not None
 
 
 class MSSQLExecutionContext_pyodbc (MSSQLExecutionContext):    
@@ -438,7 +444,7 @@ class MSSQLDialect(ansisql.ANSIDialect):
     def preparer(self):
         return MSSQLIdentifierPreparer(self)
 
-    def get_default_schema_name(self):
+    def get_default_schema_name(self, connection):
         return self.schema_name
 
     def set_default_schema_name(self, schema_name):
@@ -487,7 +493,7 @@ class MSSQLDialect(ansisql.ANSIDialect):
     def has_table(self, connection, tablename, schema=None):
         import sqlalchemy.databases.information_schema as ischema
 
-        current_schema = schema or self.get_default_schema_name()
+        current_schema = schema or self.get_default_schema_name(connection)
         columns = self.uppercase_table(ischema.columns)
         s = sql.select([columns],
                    current_schema
@@ -506,7 +512,7 @@ class MSSQLDialect(ansisql.ANSIDialect):
         if table.schema is not None:
             current_schema = table.schema
         else:
-            current_schema = self.get_default_schema_name()
+            current_schema = self.get_default_schema_name(connection)
 
         columns = self.uppercase_table(ischema.columns)
         s = sql.select([columns],
@@ -861,6 +867,7 @@ class MSSQLCompiler(ansisql.ANSICompiler):
     def visit_alias(self, alias, **kwargs):
         # translate for schema-qualified table aliases
         self.tablealiases[alias.original] = alias
+        kwargs['mssql_aliased'] = True
         return super(MSSQLCompiler, self).visit_alias(alias, **kwargs)
 
     def visit_column(self, column):
diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py
index 08ae760fc..44329468f 100644
--- a/lib/sqlalchemy/orm/query.py
+++ b/lib/sqlalchemy/orm/query.py
@@ -300,11 +300,7 @@ class Query(object):
     def filter_by(self, **kwargs):
         """apply the given filtering criterion to the query and return the newly resulting ``Query``."""
 
-        #import properties
-        
-        joinpoint = self._joinpoint
-
-        clauses = [joinpoint.get_property(key, resolve_synonyms=True).compare(operator.eq, value)
+        clauses = [self._joinpoint.get_property(key, resolve_synonyms=True).compare(operator.eq, value)
             for key, value in kwargs.iteritems()]
         
         return self.filter(sql.and_(*clauses))