我知道这很旧…但我今天遇到了同样的问题,我找到了一个解决办法:
Model.find_by_sql
如果你想实例化结果:
Client.find_by_sql("
SELECT * FROM clients
INNER JOIN orders ON clients.id = orders.client_id
ORDER BY clients.created_at desc
")
# => [<Client id: 1, first_name: "Lucas" >, <Client id: 2, first_name: "Jan">...]
Model.connection.select_all('sql').to_hash
如果你只想要一个值的哈希值:
Client.connection.select_all("SELECT first_name, created_at FROM clients
WHERE id = '1'").to_hash
# => [
{"first_name"=>"Rafael", "created_at"=>"2012-11-10 23:23:45.281189"},
{"first_name"=>"Eileen", "created_at"=>"2013-12-09 11:22:35.221282"}
]
结果对象:
Select_all返回一个结果对象。你可以用它来变魔术。
result = Post.connection.select_all('SELECT id, title, body FROM posts')
# Get the column names of the result:
result.columns
# => ["id", "title", "body"]
# Get the record values of the result:
result.rows
# => [[1, "title_1", "body_1"],
[2, "title_2", "body_2"],
...
]
# Get an array of hashes representing the result (column => value):
result.to_hash
# => [{"id" => 1, "title" => "title_1", "body" => "body_1"},
{"id" => 2, "title" => "title_2", "body" => "body_2"},
...
]
# ActiveRecord::Result also includes Enumerable.
result.each do |row|
puts row['title'] + " " + row['body']
end
来源:
ActiveRecord -查找by
SQL。
Ruby on Rails -活动记录结果
。