How to add comments to requests with ActiveRecord?

I want to add a comment to every request send by active record in order to fo开发者_运维技巧und source in mysql slow query. How can I modify the request before ActiveRecord sends it?

For example i want to have this in my central mysql slow query log.

SELECT * FROM articles
-- File: refresh-article.rb

ActiveRecord already logs db requests with timing information to your app log.

I solve the problem with monkey patch

ActiveRecord::ConnectionAdapters::Mysql2Adapter.class_eval do
    def execute_with_log(sql, name=nil)
        sql = "-- Script: #{$0}\n#{sql}"
        execute_without_log(sql, name)
    end
    alias_method_chain :execute, :log
end

In your rails app, you can see your queries with timing in log/(production|development).log.

However if you want anything more than that, I suggest checking out NewRelic in development mode. It is free, and it shows your the source of where that query was executed(which looks like what you want). It really is one of the best logging/performance analyzer out there.

I found a solution by monkey patch MySQL2::execute

ActiveRecord 6 allows queries to be annotated

User.annotate("selecting user names").select(:name)
# SELECT "users"."name" FROM "users" /* selecting user names */

User.annotate("selecting", "user", "names").select(:name)
# SELECT "users"."name" FROM "users" /* selecting */ /* user */ /* names */

https://api.rubyonrails.org/classes/ActiveRecord/QueryMethods.html#method-i-annotate

You could combine this with the caller_locations kernel method:

User.annotate("#{caller_locations(1,1).first}").select(:name)

https://www.rubydoc.info/stdlib/core/2.0.0/Kernel:caller_locations