Get all records with child records OR field length > 250

Question

I have a Comment model which has-many attachments. What I want to return, is all of the comments which either have one or more attachment records, OR whose comment is longer than 250 characters.

Is there any way I can do this without writing it entirely in pure SQL? I'm struggling to build up a WHERE clause in just the rails method. It's not quite as simple as I'd hoped :(

Ideally I want this to be a scope but whatever will work is fine

Answer 1

Jump into the irb or rails c (console) do this from command-line to get it then plug it in.

 c     =  YourCommentModel.where('attachments > ?', 1)
len250 =  c = YourCommentModel.where('attachments.length> ?', 250)

first one gives comments of greater than 1, second gives comments > 250

Answer 2

You could try:

Comment.includes(:attachments).where('attachments.comment_id IS NOT NULL OR LEN(comments.content) > 250')

Answer 3

The WHERE clause should follow the pattern o the following pseudo-code

WHERE Length(Comment_field) > 250
OR EXISTS (Select COMMENT_ID from attachments)