Interoperability with IBM Host Systems

Host Data Access Using OLE DB

SNA Server provides record-level access to mainframe and AS/400 files using the OLE DB Provider for AS/400 and VSAM feature.

Leveraging the advantages of OLE DB as a common interface to dissimilar data sources, as shown in Figure 10.29, OLE DB Provider for AS/400 and VSAM lets you:

Customize solutions for reading from and writing to AS/400 and mainframe file systems without first migrating the information to the client/server platform.
Integrate nonstructured data with desktop and server-based databases and tools.
Develop applications using high-level interfaces, such as Microsoft® ActiveX® Data Objects (ADO), which support Microsoft® Visual Basic® (VB), Microsoft® Visual C++® (VC++), Microsoft® Visual J++^™ (VJ++), Microsoft® Visual Basic® for Applications (VBA), and Microsoft Scripting.

By providing applications with the ability to access and manipulate host files at the record level, you can leverage investments in host-based storage, management, backup, and security systems.

Enlarge figure

Figure 10.29 Host Data Access Using OLE DB Provider for AS/400 and VSAM

OLE DB Provider uses the record-level input/output (RLIO) protocol of the IBM Distributed Data Management (DDM) architecture (level 2 and higher). This feature is implemented as a source DDM requester and is interoperable with target DDM server implementations on most popular host environments, including MVS/ESA, OS/390, and OS/400.

Client applications communicate with a host database through an APPC (LU 6.2) connection to the host system established between the SNA Server Client software and SNA Server.

OLE DB Provider supports the following features:

File and record locking
File and record attribute preservation
Indexed and sequential record access
Fixed and variable logical record length

OLE DB Provider supports a variety of data file types for mainframe and AS/400 systems. For mainframe systems, OLE DB Provider supports SAM data sets, including BSAM and QSAM; VSAM data sets, including ESDS, KSDS, RRDS, VRRDS; alternate index for ESDS and KSDS data sets; and PDS/PDSE members. For AS/400, OLE DB Provider supports keyed and non-keyed physical files and logical files.

Complete information about using the OLE DB Provider for VSAM and AS/400 is provided in the SNA Server Software Development Kit, included with SNA Server.