Changes in the Database after applying the hotfix no. 30 for version 7
As we do not want to store the same data in the database multiple times (to avoid duplicity) we are also doing some changes on-the-fly directly via hotfixes. These are not major changes, just minor ones, but in some cases, this could affect your custom code depending on the database fields you are using.
If you add a field to any document type, e.g. CMS.News with the form control - multiple categories selector, you can add categories to your document in the CMS desk. But if you were getting the categories directly from this DB field, you will find out that categories are not in the DB after applying the hotfix. The values are not saved in the extra field of the document type anymore.
The change is related to one older bug which leads to removing duplicate entries from the Database because they are already stored in a different place.
Related categories are stored in the CMS_DocumentCategory
If you want to get the Document Categories you will just need to use a different API method:
InfoObjectCollection categories = CMS.DocumentEngine.DocumentHelper.GetDocument(int documentID, new TreeProvider(CMSContext.CurrentUser)).Categories;
See also: Categories DB tables
, Documents DB tables
Kentico CMS 7.30