I have a user table in Postgresql database, if run User.count, it takes 150ms to get result. It is too too slow to us. Ideally, it shall take less than 10ms to return me the result. Is there any way to cache sql result in model level? Something like
def self.total_count
User.count.cached # that's my imagination
end
In my opinion, there are several ways you could go about this -
If your table is extremely big and accuracy is not the most important thing, you also look into Postgres' COUNT ESTIMATE query.
SELECT reltuples AS approximate_row_count FROM pg_class WHERE relname = 'users';
You should look into counter_cache. It will work great if your user belongs_to another model http://guides.rubyonrails.org/association_basics.html