Obsolete Data Access Technologies

Obsolete Data Access Technologies

The following section is taken from the Microsoft Data Access Technologies Road Map.

Obsolete technologies are technologies that have not been enhanced or updated in several product releases and that will be excluded from future product releases. Do not use these technologies when you write new applications. When you modify existing applications that are written by using these technologies, consider migrating those applications to ADO.NET.

The following components are considered obsolete:

  • DB-Library: This is a SQL Server–specific programming model that includes C APIs. There have been no feature enhancements to the DB-Library since SQL Server 6.5. Its final release was with SQL Server 2000, and it will not be ported to the 64-bit Windows operating system. 
  • Embedded SQL (E-SQL): This is a SQL Server–specific programming model that enables Transact-SQL statements to be embedded in Visual C code. No feature enhancements have been made to the E-SQL since SQL Server 6.5. Its final release was with SQL Server 2000, and it will not be ported to the 64-bit Windows operating system. 
  • Data Access Objects (DAO): DAO provides access to JET (Access) databases. This API can be used from Microsoft Visual Basic, Microsoft Visual C++, and scripting languages. It was included with Microsoft Office 2000 and Office XP. DAO 3.6 is the final version of this technology. It will not be available on the 64-bit Windows operating system. 
  • Remote Data Objects (RDO): RDO was designed specifically to access remote ODBC relational data sources, and made it easier to use ODBC without complex application code. It was included with Microsoft Visual Basic versions 4, 5, and 6. RDO version 2.0 was the final version of this technology.

64 bit not possible in these older technologies

Some things to keep in mind about these older database technologies is that they were never built for Windows Vista or 64 bit Windows. If you are referencing these libraries today your application will probably not run on future versions of Windows.

In a few cases flagging your application as x86 only will force your .Net assembly to run in 32 bit mode on 64 bit Windows and allow these technologies to work, but don't always count on it. 32 bit Windows Vista ships with Jet drivers, but 64 bit Windows Vista does not include even the 32 bit drivers by default. This means you will have frustrated users trying to find runtime providers that either do not exist, or are not supported.

VistaDB can run 32 and 64 bit from a single .Net assembly!