Remove comment that is no longer relevant.

This commit is contained in:
Guo Xiang Tan 2017-09-14 19:57:50 +08:00
parent 4e49b3b140
commit de46d59a94

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@ -285,15 +285,6 @@ class TopicQuery
end
def self.unread_filter(list, user_id, opts)
# PERF note
# We use the function first_unread_topic_for here instead of joining
# the table to assist the PostgreSQL query planner
#
# We want the query planner to have the actual value of the first_unread_topic so
# it can pick an appropriate plan. If it does not have this upfront it will just assume
# that the value will be 1/3 of the way through the topic table which makes it use terrible
# indexes for the plan.
#
col_name = opts[:staff] ? "highest_staff_post_number" : "highest_post_number"
list