This document details the steps required to provide Microsoft Entity Framework access to Ingres Schema Objects using the
The following prerequisites must be in place for this solution to be possible.
An Ingres DBMS hosting the required Schema Objects needs to be available. In this document, the Ingres Tutorial sample database will be used to demonstrate the process.
An Ingres ODBC Driver is required for Linking the Ingres Schema Objects into the Virtuoso Server.
ingiima will be assumed to exist on the machine hosting the Virtuoso Server.
An Virtuoso installation including the Virtuoso Universal Server and ADO.NET Entity Framework Provider is required. The Virtuoso components used must be Release 5.10.x or above, this being the minimum version containing support for Microsoft Entity Frameworks.
Microsoft Visual Studio 2008 Service Pack 1 is required, this being the only version containing the necessary Entity Framework support available at the time of writing.
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 tables to be used are defined as not nullable in the Ingres database schema before attempting to generate an EDM. In the case of the Ingres Tutorial database, all primary keys are not nullable. Thus, this should not be an issue in this case.
The Virtuoso Virtual Database engine uses ODBC as the connectivity mechanism for linking remote database objects into its local schema.
Thus, an Ingres ODBC Driver must be available with a suitably configured DSN for connecting to the target database.
Installation instructions for the
In the event that no entity-linking associations are automatically created (as is the case here with Ingres), the associations will need to be created manually. The following document details this process —
Now that a Microsoft Entity Data Model has been created for the Ingres Tutorial database, Entity Framework applications can be created to make use of it.