One table vs multiple tables
I have the following tables: - posts - files - events - documents Every post, file, event, document can have comments. What is the better database scheme for this, and why ? First solution comments table (comment_id, author_id, comment) 4 tables to create relations (posts_comments(post_id, comment_id), files_comments(file_id, comment_id), events_comments(event_id, comment_id), documents_comments(document_id, comment_id)) Second solution comments table (comment_id, author_id, comment) items_comments (comment_id, parent_type (enum['post', 'file', 'event', 'document']), parent_id) What is a