Remove submodule, just put Dependencies in ./libs

2011-02-28 15:25:42 +01:00
parent 2fb578d4de
commit 6888798ef6
541 changed files with 173394 additions and 4 deletions
@@ -0,0 +1,97 @@
+# mssql/mxodbc.py
+# Copyright (C) 2005-2011 the SQLAlchemy authors and contributors <see AUTHORS file>
+#
+# This module is part of SQLAlchemy and is released under
+# the MIT License: http://www.opensource.org/licenses/mit-license.php
+
+"""
+Support for MS-SQL via mxODBC.
+
+mxODBC is available at:
+
+    http://www.egenix.com/
+
+This was tested with mxODBC 3.1.2 and the SQL Server Native
+Client connected to MSSQL 2005 and 2008 Express Editions.
+
+Connecting
+~~~~~~~~~~
+
+Connection is via DSN::
+
+    mssql+mxodbc://<username>:<password>@<dsnname>
+
+Execution Modes
+~~~~~~~~~~~~~~~
+
+mxODBC features two styles of statement execution, using the
+``cursor.execute()`` and ``cursor.executedirect()`` methods (the second being
+an extension to the DBAPI specification). The former makes use of a particular
+API call specific to the SQL Server Native Client ODBC driver known
+SQLDescribeParam, while the latter does not.
+
+mxODBC apparently only makes repeated use of a single prepared statement
+when SQLDescribeParam is used. The advantage to prepared statement reuse is
+one of performance. The disadvantage is that SQLDescribeParam has a limited
+set of scenarios in which bind parameters are understood, including that they
+cannot be placed within the argument lists of function calls, anywhere outside
+the FROM, or even within subqueries within the FROM clause - making the usage
+of bind parameters within SELECT statements impossible for all but the most
+simplistic statements.
+
+For this reason, the mxODBC dialect uses the "native" mode by default only for
+INSERT, UPDATE, and DELETE statements, and uses the escaped string mode for
+all other statements. 
+
+This behavior can be controlled via
+:meth:`~sqlalchemy.sql.expression.Executable.execution_options` using the
+``native_odbc_execute`` flag with a value of ``True`` or ``False``, where a
+value of ``True`` will unconditionally use native bind parameters and a value
+of ``False`` will uncondtionally use string-escaped parameters.
+
+"""
+
+import re
+import sys
+
+from sqlalchemy import types as sqltypes
+from sqlalchemy import util
+from sqlalchemy.connectors.mxodbc import MxODBCConnector
+from sqlalchemy.dialects.mssql.pyodbc import MSExecutionContext_pyodbc
+from sqlalchemy.dialects.mssql.base import (MSExecutionContext, MSDialect, 
+                                            MSSQLCompiler,
+                                            MSSQLStrictCompiler,
+                                            _MSDateTime, _MSDate, TIME)
+
+
+
+class MSExecutionContext_mxodbc(MSExecutionContext_pyodbc):
+    """
+    The pyodbc execution context is useful for enabling
+    SELECT SCOPE_IDENTITY in cases where OUTPUT clause
+    does not work (tables with insert triggers).
+    """
+    #todo - investigate whether the pyodbc execution context
+    #       is really only being used in cases where OUTPUT
+    #       won't work.
+
+class MSDialect_mxodbc(MxODBCConnector, MSDialect):
+
+    # TODO: may want to use this only if FreeTDS is not in use,
+    # since FreeTDS doesn't seem to use native binds.
+    statement_compiler = MSSQLStrictCompiler
+    execution_ctx_cls = MSExecutionContext_mxodbc
+    colspecs = {
+        #sqltypes.Numeric : _MSNumeric,
+        sqltypes.DateTime : _MSDateTime,
+        sqltypes.Date : _MSDate,
+        sqltypes.Time : TIME,
+    }
+
+
+    def __init__(self, description_encoding='latin-1', **params):
+        super(MSDialect_mxodbc, self).__init__(**params)
+        self.description_encoding = description_encoding
+
+dialect = MSDialect_mxodbc
+