Hi Steven

We have had some performance issues deleting CatalogNodes, and we have found out that there are different ways of deleting them.

Could you share some code showing how you try to delete the categories?

We are using the ICatalogSystem.DeleteCatalogNodesAndEntries() method to delete the CatalogNodes. We tried using the ICatalogSystem.DeleteCatalogNode metod as well. That also seems to work, but it does a lot of in-memory work with the catalog structure, and in our case where we needed to delete a large number of CatalogNodes durin our catalog import, this gave us major performance issues. DeleteCatalogNodesAndEntries() uses stored procedures to delete the data. The method name also suggests that it may delete CatalogEntries as well as nodes. In our case that is not an issue, because we have already removed any relevant CatalogEntries from the catalog structure before we do the deletion (we do the work during catalog import).

If you are using the Content API instead, the code above may not be relevant for you.

Regards

Anders Kåre Olsen

It can be a pretty tricky, as if you receive the event after the node is deleted, then it's impossible to call DeleteCatalogNodesAndEntries(). If you can listen to Deleting event, aka before the node is deleted, then it's an option.

Another option is to listen to RelationDeleted event. From the event you can get the CatalogRelationDto (cast source object), get the NodeEntryRelation, then get the entry ids and delete them.

I am using the content api.  What I have today is on the deleting content event, I execute an extension function on the ContentRepository class that deletes the children of the current node for a specific type.  

      private static void DeletingCategoryNode(object sender, DeleteContentEventArgs eventArgs)
        {
            var content = eventArgs.Content as CategoryNode;
            //how to recursively delete category?
            if (content != null)
            {
                //delete child category    
                var contentRepo = ServiceLocator.Current.GetInstance<IContentRepository>();
                contentRepo.DeleteChildren<CategoryNode>(content.ContentLink);
            }
        }

       public static void DeleteChildren<T>(this IContentRepository contentRepository, ContentReference contentLink) where T : class, IContent
        {
            var children = contentRepository.GetDescendents(contentLink);
            foreach (var childRef in children)
            {
                var child = contentRepository.Get<T>(childRef);
                if (child != null)
                {
                    contentRepository.Delete(child.ContentLink, false);
                }
            }
        }

I've been advocating the uses of Content APIs - but this is the place where ICatalogSystem.DeleteCatalogNodesAndEntries works better. Use ReferenceConverter.GetObjectId(nodeContentLink) to get the node id and pass to that method, and you're good to go