Question

Let’s say I have two tables, news and comments.

news (   id,   subject,   body,   posted )  comments (   id,   parent,  // points to news.id   message,   name,   posted ) 

I would like to create one query that grabs the latest x # of news item along with the name and posted date for the latest comment for each news post.

Speed matters in terms of selecting ALL the comments in a subquery is not an option.

Answer 1

I just realized the query does not return results if there are no comments attached to the news table, here’s the fix as well as an added column for the total # of posts:

SELECT news.*, comments.name, comments.posted, (SELECT count(id) FROM comments WHERE comments.parent = news.id) AS numComments FROM news LEFT JOIN comments ON news.id = comments.parent AND comments.id = (SELECT max(id) FROM comments WHERE parent = news.id)