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  • VOS.VirtSybaseEntityFrameworkUsage(Last) -- DAVWikiAdmin? , 2017-06-29 07:41:27 Edit WebDAV System Administrator 2017-06-29 03:41:27

    Using Microsoft Entity Frameworks to Access Sybase Schema Objects with Virtuoso

    This document details the steps required to provide Microsoft Entity Framework access to Sybase Schema Objects using the OpenLink Virtuoso Universal Server. This is achieved by linking the required Sybase Schema objects into Virtuoso using its built in Virtual Database engine, and then using the Virtuoso ADO.NET Entity Framework provider to query the remote Sybase Schema objects linked into the Virtuoso Server.

    Prerequisites

    The following must be in place to complete this exercise.

    1. Microsoft Visual Studio 2008 SP1 (or later)
      Microsoft Visual Studio 2008 Service Pack 1 (or later) is required, as previous versions do not include the necessary Entity Framework support.

    2. Virtuoso ADO.NET Entity Framework Provider, v5.10 or later
      The ADO.NET Entity Framework Provider must be installed on the Visual Studio development and deployment host(s). Version 5.10.x or later is required, as previous versions do not include the necessary Entity Frameworks support.

    3. Virtuoso Universal Server, v5.10 or later
      Virtuoso Universal Server Release 5.10 or later is required, as previous versions do not include the necessary Entity Frameworks support. This may be on any host which is TCP/IP accessible from the Visual Studio development and deployment host(s).

    4. ODBC Driver for Sybase
      The Virtuoso Server uses an ODBC Driver for Sybase to link in the Sybase Schema Objects. The OpenLink Single-Tier ODBC Driver for Sybase will be used in this document, and a functional ODBC Data Source Name (DSN) of "syb15ma" will be assumed to exist on the machine hosting the Virtuoso Server. Any ODBC compliant driver for Sybase should work.

    5. Sybase DBMS
      A Sybase DBMS hosting the required Schema Objects needs to be available. This may be on any host which is TCP/IP accessible from the Virtuoso Server host. In this document, the Sybase pubs2 database will be used to demonstrate the process.

    Tasks

    1. Ensure Sybase Primary Keys (PKs) are not nullable
      The Visual Studio 2008 Entity Data Model (EDM) requires that all primary keys are NOT Nullable. Visual Studio 2008 will fail to generate an EDM if any are. Therefore, ensure any primary keys to be used are defined as not nullable in the Sybase database schema before attempting to generate an EDM. In the case of the Sybase pubs2 database all primary keys are non nullable. Thus, this should not be an issue in this case.

    2. Install and configure the OpenLink ODBC Driver for Sybase

    3. Install and configure OpenLink Virtuoso Universal Server

    4. Link Sybase tables and other schema objects into OpenLink Virtuoso

    5. Create a Visual Studio-hosted Entity Data Model (EDM)

      If entity-linking associations (i.e., Foreign Keys) are not automatically created (as they are not here with Sybase), the associations must be created manually.

    6. Use the EDM to create an Entity Frameworks-based ADO.NET Data Service

    7. Use the EDM to create an Entity Frameworks-based Windows DataGrid Form Application

    CategoryDocumentation CategoryVirtuoso CategoryEntityFrameworks CategoryDotNET CategorySybase