I'm a bit confused about the way Knowledge Articles work. To try them out, I've created an Article type, added a single custom field and created a draft article with some dummy data. The goal is to retrieve this article using SOQL in Apex. I manage to query some standard fields by using something like this
SELECT Id,Title,UrlName,Summary,KnowledgeArticleId FROM KnowledgeArticleVersion WHERE Language ='en_US' AND PublishStatus ='Draft'
but when I try to query the custom field, I get an error saying this field doesn't exist. What is the correct way to go about this?