- changed a few isinstance(value, Decimal) to "is not None", where appropriate

- fixed result processor for Numeric(asdecimal=False) on MSSQL.

4 files changed, 12 insertions, 6 deletions

diff --git a/lib/sqlalchemy/dialects/mssql/base.py b/lib/sqlalchemy/dialects/mssql/base.py
index 6c8937799..bd275d758 100644
--- a/lib/sqlalchemy/dialects/mssql/base.py
+++ b/lib/sqlalchemy/dialects/mssql/base.py
@@ -286,8 +286,14 @@ class _MSNumeric(sqltypes.Numeric):
                     return value
             return process
         else:
+            #XXX: if the DBAPI returns a float (this is likely, given the
+            # processor when asdecimal is True), this should be a None
+            # processor instead.
             def process(value):
-                return float(value)
+                if value is not None:
+                    return float(value)
+                else:
+                    return value
             return process
 
     def bind_processor(self, dialect):
diff --git a/lib/sqlalchemy/dialects/mysql/mysqldb.py b/lib/sqlalchemy/dialects/mysql/mysqldb.py
index 846de6580..c07ed8713 100644
--- a/lib/sqlalchemy/dialects/mysql/mysqldb.py
+++ b/lib/sqlalchemy/dialects/mysql/mysqldb.py
@@ -50,9 +50,9 @@ class MySQL_mysqldbCompiler(MySQLCompiler):
 class _DecimalType(_NumericType):
     def result_processor(self, dialect, coltype):
         if self.asdecimal:
-            return
+            return None
         def process(value):
-            if isinstance(value, decimal.Decimal):
+            if value is not None:
                 return float(value)
             else:
                 return value
diff --git a/lib/sqlalchemy/dialects/mysql/oursql.py b/lib/sqlalchemy/dialects/mysql/oursql.py
index 5558c1a19..79a36f535 100644
--- a/lib/sqlalchemy/dialects/mysql/oursql.py
+++ b/lib/sqlalchemy/dialects/mysql/oursql.py
@@ -38,9 +38,9 @@ class _PlainQuery(unicode):
 class _oursqlNumeric(NUMERIC):
     def result_processor(self, dialect, coltype):
         if self.asdecimal:
-            return
+            return None
         def process(value):
-            if isinstance(value, decimal.Decimal):
+            if value is not None:
                 return float(value)
             else:
                 return value
diff --git a/lib/sqlalchemy/dialects/postgresql/pypostgresql.py b/lib/sqlalchemy/dialects/postgresql/pypostgresql.py
index 2c33b3eb5..77ed44512 100644
--- a/lib/sqlalchemy/dialects/postgresql/pypostgresql.py
+++ b/lib/sqlalchemy/dialects/postgresql/pypostgresql.py
@@ -22,7 +22,7 @@ class PGNumeric(sqltypes.Numeric):
             return None
         else:
             def process(value):
-                if isinstance(value, decimal.Decimal):
+                if value is not None:
                     return float(value)
                 else:
                     return value