在查詢輸出

Question

字段太多我有一個查詢，我只希望輸出三個變量

Relationship.select('follower_id as source, followed_id as target, value').map(&:attributes) 

但是我得到的結果包括id變量如下，我不想。我如何擺脫它？

{"source"=>1, "target"=>3, "value"=>1, "id"=>nil}, 
{"source"=>1, "target"=>4, "value"=>1, "id"=>nil}, 
{"source"=>1, "target"=>5, "value"=>1, "id"=>nil}, 
{"source"=>2, "target"=>3, "value"=>1, "id"=>nil} 

Answer 1

select總是返回id屬性，你可以在map擺脫它：

Relationship.select('follower_id as source, followed_id as target, value').map{|x| [x.source, x.target, x.value]}