turning the decimals to floats allows the E notation to work with sybase+pyodbc for small E notations

1 files changed, 26 insertions, 0 deletions

diff --git a/lib/sqlalchemy/dialects/sybase/pyodbc.py b/lib/sqlalchemy/dialects/sybase/pyodbc.py
index 1bb09251c..61cf333da 100644
--- a/lib/sqlalchemy/dialects/sybase/pyodbc.py
+++ b/lib/sqlalchemy/dialects/sybase/pyodbc.py
@@ -31,6 +31,26 @@ Currently *not* supported are::
 from sqlalchemy.dialects.sybase.base import SybaseDialect, SybaseExecutionContext
 from sqlalchemy.connectors.pyodbc import PyODBCConnector
 
+import decimal
+from sqlalchemy import processors, types as sqltypes
+
+# TODO: should this be part of pyodbc connectors ??? applies to MSSQL too ?
+class _SybNumeric(sqltypes.Numeric):
+    def bind_processor(self, dialect):
+        super_process = super(_SybNumeric, self).bind_processor(dialect)
+        
+        def process(value):
+            if self.asdecimal and \
+                    isinstance(value, decimal.Decimal) and \
+                    value.adjusted() < -6:
+                return processors.to_float(value)
+            elif super_process:
+                return super_process(value)
+            else:
+                return value
+        return process
+
+
 class SybaseExecutionContext_pyodbc(SybaseExecutionContext):
     def set_ddl_autocommit(self, connection, value):
         if value:
@@ -39,7 +59,13 @@ class SybaseExecutionContext_pyodbc(SybaseExecutionContext):
             connection.autocommit = False
 
 
+
 class SybaseDialect_pyodbc(PyODBCConnector, SybaseDialect):
     execution_ctx_cls = SybaseExecutionContext_pyodbc
 
+    colspecs = {
+        sqltypes.Numeric:_SybNumeric,
+        sqltypes.Float:sqltypes.Float,
+    }
+
 dialect = SybaseDialect_pyodbc