Thank you for your inquiry. Please note that GroupDocs.Annotation is platform independent and a storage-agnostic API, this means that it does not support any specific storage (i.e. Oracle, MS SQL Server and so on). But it provides abstract interface that you can implement, and use for storing data in specific storage. We have also developed some sample showcase projects for your ease here which saves annotations in the JSON file, as these showcases are open-source, you may enhance them to any extent or as per your use-case.
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