In general, content types will be defined in the development phase of your content model. They are the "backbone" of your CoreMedia application and therefore are assumed to be stable. Nevertheless, new requirements might demand changes in the content model while preserving the existing content. In this chapter you will find a description on how to add, rename and remove content types and attributes to and from your content model.
![[Caution]](../common/images/caution.png) | Caution |
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Always make a backup of your data before schema migration. Stop the Content Server when you change content types. The changes take effect not until the Content Server has been started. Choose log level "Debug" and check the server log file for the impact of the new content types. |
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