rails - activerecord SELECT TOP 1 field_name * FROM table_name

Question

I have a sql like this:

SELECT TOP 1 field_name * FROM table_name

and I want to covert it into activerecord in rails.

Answer 1

That code doesn't do the job?

YourModel.select(:field_name).first

or

YourModel.select(:field_name).order('id desc').first

Answer 2

只需使用limit(1)或first ：

Model.select(:field_name).limit(1)

Answer 3

pick (Rails 6+)

Since Rails 6, you can use the following:

YourModel.order(id: :desc).pick(:field_name)

pick is even more efficient than

YourModel.select(:field_name).order('id desc').first

since, it will only load the actual value, not the entire record object.

For more details, please, follow this link to docs .

Also, there is a reference to the corresponding PR .