PG: What's your current take on reddit's comment system?

Post by clueless » Sun, Jul 15, 2007, 4:19 PM UTC

vlad wrote: post #23

nostrademons wrote: post #21

Earlier quoted context omitted.

How do you get the full thread for a given parent? Selecting based on the parentid alone gives you only immediate descendants. Recursive queries are generally a no-no, as they drag your performance down fairly quickly. Selecting based on the newsid gives you every single comment on the item, and then you'll have to do a lot of work (basically building up the full tree structure in memory) to find out which are childr…

You would find the full thread by searching for comments with the appropriate newsid. To simplify the recursive function (using data in memory, not in the database), you could also have another field, called indent, that stores the level in the comments. You could find all the comments with one SQL statement (where newsid = news.id), then go through each level of each comment, and sort it that way. You could even mak…

 in html for that.

Post by Jd » Sun, Jul 15, 2007, 5:55 PM UTC

whacked_new wrote: post #62

Jd wrote: post #56

Earlier quoted context omitted.

Here's one model I'd be interested in testing. Three roles: basic, member, and administrator. Each account has karma (natural numbers), but the exact of karma is invisible to all except the administrator. There is a karma meter which displays karma as a color gradient with different levels assigned different colors. Content rating is done on a color gradient, from white to blue. Blue is good, white is bad, light blue…

Similar, but a non-karma karma system. :) One thing though, I am fairly uncertain about the color gradient. In the beginning I used red-green. But some cultures have the order reversed, and total red and total green excite the eyes differently. Then I opted for using colorless-color (white-"gold", since gold is supposed to be culture-neutral), but when I showed some people they were confused and told me to use red-gr…

Post by dantheman » Mon, Jul 23, 2007, 2:17 PM UTC

Post by twism » Sat, Aug 18, 2007, 9:17 PM UTC

nostrademons wrote: post #32

Jd wrote: post #29

Earlier quoted context omitted.

Just thinking off the cuff here, but couldn't one store a lisp-style list as a string in a relational database. If I was using Ruby on Rails, I could simply build a simple lisp interpreter in Ruby to parse the string, then capture it as an in-memory tree. This way I would only have active items in memory and could use some of the advantages of the standard web development platforms for whatever else I was doing. Edit…

Sure you could. You could also select all comments on the item and rebuild the tree in-memory, as Vlad suggests elsewhere on this thread. The code isn't even as hard as I'd thought it'd be: comments = dbh.query('SELECT * FROM comments WHERE news_id = $newsid') response_tree = {} for comment in comments: comment.children = [] response_tree[comment.id] = comment for comment in comments: response_tree[comment.parent_id]…