Using Version 9 Applications With Mimer SQL Version 10
A Mimer SQL version 9 application is linked with the MIMDB9 shared library which provides client-side functionality for the application. The MIMDB9 shared library communicates with the database server.
The API exported by the MIMDB9 library is compatible with the new MIMDB library used in version 10. Likewise the client/server protocol used between the MIMDB9/MIMDB libraries and the database server is also compatible between versions. This means that there are several ways to run a Mimer SQL version 9 application with a Mimer SQL version 10 server.
Relink the Application
The preferred method is to relink the version 9 application with the new MIMDB shared library. This will make the application a true version 10 application and eliminate the setup needed by the other approaches.
This is the preferred method if the sources or object files of the application is still available.
Remap the Shareable Libraries
By defining the logical name MIMDB9 to point to MIMDB, all version 9 applications will use the new MIMDB shared library$ DEFINE MIMDB9 MIMDB
(Define the logical name in the SYSTEM or GROUP logical name tables as appropriate.)
This method is very similar to relinking the application, but requires extra setup. This setup will also affect all version 9 applications simultaneously, which may lead to undesired effects unless care is exercised.
Continue With the Old Shared Library
Since the client/server protocol used between the MIMDB9 shared library and the database server is compatible between version 9 and version 10, the old version 9 application can access the version 10 server directly. There is no need to do anything special to the version 9 application.
The drawback with this method is that new features, optimizations and bug corrections in the new MIMDB shared library will not be available to the application; it will function as it did before and rely on the compatibility of the client/server protocol.
This method works for all kinds of communication protocols available; shared-memory, TCP/IP and DECNET. There is no need to do anything special in the SQLHOSTS file for this to work.
However, be aware that if you should try to access a database in single-user mode, the MIMDB9 shared library will map the version 9 single-user library. This library will fail if it tries to open a version 10 database in single-user mode.
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