This article describes the limitations of the current
version of Microsoft ODBC Driver and OLE DB Provider for Oracle. These
components are currently in maintenance mode. No new updates are planned for
future releases of these components including their support against versions
later than Oracle 8i.
The current version of the Microsoft ODBC Driver for Oracle complies with the
ODBC 2.5 specification, while the OLE DB Provider for Oracle is a native Oracle
7 OCI API provider. Both the driver and provider make OCI 7 API calls against
the Oracle client components regardless of the Oracle version installed on the
From Microsoft Data Access Components (MDAC) version 2.5 and later versions, both the Microsoft ODBC Driver and OLE DB Provider support ONLY Oracle 7 and Oracle 8i with the following limitations:
- Oracle 8.x-specific data types, such as CLOB, BLOB, BFILE, NCHAR, NCLOB, and NVARCHAR2, are not supported.
- The Unicode feature against Oracle 7.x and 8.x servers is
- Multiple Oracle client instances, or multiple Oracle homes, are not supported because they rely on the first occurrence of the Oracle home in the SYSTEM PATH variable.
- Returning multiple resultsets from a stored procedure or batch SQL statement is not supported using ADO or OLEDB.
For additional information about how to retrieve a resultset from an Oracle stored
procedure, click the following article numbers to view the articles in the Microsoft Knowledge Base:
How to retrieve ADO recordset from
Oracle through ASP using REF CURSORS
HOWTO: Retrieve Recordsets from Oracle Stored Procs Using ADO
- Nested outer joins are not supported.
- XML persistence is not supported.
- Version greater than 8i are not supported using this drivers.
new Microsoft .NET Managed Oracle Provider that supports the Oracle 9i client
is now available. To download this provider, visit the following Microsoft Web site:http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=4F55D429-17DC-45EA-BFB3-076D1C052524
For additional information, see the Help file that is
included with the driver and provider.
For additional information, click the following article numbers to view the articles in the Microsoft Knowledge Base:
Techniques to debug connectivity issues to an Oracle server using
the ODBC Driver and OLE DB Provider
How to set
up and troubleshoot a linked server to Oracle in SQL Server
Returning multiple resultsets fails under ADO with Microsoft Oracle OLEDB
Provider and ODBC Driver
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.