Almost every Siebel CRM project is bound to undergo an upgrade to a newer major release in the long term. For example, a project team that may have started with Siebel CRM version 7.8 could have to face the challenge of upgrading to version 8.2 (or later versions).

Every time when the first two digits of the version number change, which is considered an upgrade as opposed to a patch, which only increases the last two digits, a new version of the Siebel Repository is delivered from Oracle.

The main effort of a Siebel CRM upgrade project is the so-called Repository Merge process during which the changes made by customers and Oracle engineers to the prior standard repository are analyzed and applied to the new customer repository. The following diagram depicts the merge process using versions 7.8 and 8.1 as an example:

We can observe that any object definition created by custom developers is copied to the New Customer Repository, which is the working repository in the...