I intend to import an Informix Dynamic Server 7.31 Database into Oracle; In this case it's the database of an old system which is not in use anymore, so the purpose is strictly readonly.
No triggers, few procedures and functions.
I'd like to import the data into Oracle 11g, is this possible or do I have to import into 10g and then upgrade to 11g?
The docs say the migration workbench is the tool of choice, is there anyone who can provide me with some experience?
How do I verify the migration was successful and the data was imported exactly the way it was?
the only supported versions for the workbench are 9i and 10g.
However, this is only for running the workbench itself and creating the repository. If you do an offline migration then you can run the scripts created by the migration utility in any version of Oracle and load the data using any version of SQL*Loader.
It may be that you can create the repository for the 10.10.4 workbench in an 11g database but I've never tried it.
As for testing there is a section in the documentation -
Oracle® Migration Workbench User’s Guide Release 10.1.0.4 for Microsoft Windows 98/2000/NT/XP and Linux x86
Chapter 7 - Testing the Oracle Database
that discusses how you can test the migrated data.
I've only ever run small test migrations and issues can depend on the complexity of the data and particularly stored procedures and embedded SQL.
If you have no triggers, few procedures and functions then it should be fairly straightforward.
It is planned to include Informix migration in a later version of SQL*Developer but there is no date for that yet.