Removing specific items from array with MongoDB
If you can identify the comment item by matching userid, name or comment -- then you can remove that comment using update() command with $pull modifier along with the appropriate condition.
If you cannot do as above, include an unique id in the comments (like UUID).
To delete the comment, do the following:
db.coll.update({<cond to identify document}, {$pull: {'comments': {'name': <name>}}} )If you use the id, which is preferred:
db.coll.update({<cond to identify document}, {$pull: {'comments': {'id': <id>}}} )
maybe you can remove comment by its 'created_at' time, as the time is unique.
$db.coll.update({cond to identify document},{$pull:{'comments':{'created_at':<>}}})
I think, you have add mongodb id to each comment when insert it. You can create a new mongodb id like this;
$comment_id = new MongoID();Now, you can delete comments by id with $pull + $update like @smoorthy's answer.