If you need to flush the cache when you edit/add/delete a record in your custom table (the Custom tables module), the cache key is not ‘<custom table class name>|all’, but ‘customtableitem.<custom table class name>|all’.

You can check the class name of your custom table in the ‘CMS_Class’ table in your Kentico database.

More information about cache dependencies: Deep dive: Cache dependencies
 

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