Multi-tiered Comment Replies: Display and Storage

Question

So I\'m trying to create a comment system in which you can reply to comments that are already replies (allowing you to create theoretically infinite threads of replies). I want

Answer 1

In database, you may create a table with foreign key column (parent_comment), which references to comments table itself. For example:

CREATE TABLE comments (
  id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
  parent_comment INT FOREIGN KEY REFERENCES comments(id),
  date_posted  DATETIME,
  ...)

In order to show comments to single item, you'll have to select all comments for particular item, and parse them recursively in your script with depth-first algorithm. Chronological order should be taken into account in traversal algorithm.