discourse/script/micro_bench.rb
Daniel Waterworth 55a1394342 DEV: pluck_first
Doing .pluck(:column).first is a very common pattern in Discourse and in
most cases, a limit cause isn't being added. Instead of adding a limit
clause to all these callsites, this commit adds two new methods to
ActiveRecord::Relation:

pluck_first, equivalent to limit(1).pluck(*columns).first

and pluck_first! which, like other finder methods, raises an exception
when no record is found
2019-10-21 12:08:20 +01:00

29 lines
554 B
Ruby

# frozen_string_literal: true
require 'benchmark/ips'
require File.expand_path("../../config/environment", __FILE__)
conn = ActiveRecord::Base.connection.raw_connection
Benchmark.ips do |b|
b.report("simple") do
User.first.name
end
b.report("simple with select") do
User.select("name").first.name
end
b.report("pluck with first") do
User.pluck_first(:name)
end
b.report("pluck with limit") do
User.pluck_first(:name)
end
b.report("raw") do
conn.exec("SELECT name FROM users LIMIT 1").getvalue(0, 0)
end
end