Activerecord group by count和user

Activerecord group by count和user_id(Activerecord group by count and user_id)

我有两个带有has_many关联的模型。

User :has_many foos Foo :belongs_to user

Foo.joins（：用户）

我希望在Foo上有一个组，它返回count和user_id。 意味着我想知道'user_id'有多少'foos'。

例如：

user_id foos_count ------------- 1 31 2 52

I have two models with has_many associations.

User :has_many foos Foo :belongs_to user

Foo.joins(:user)

I want to have a group by on Foo, where it returns with count and user_id. Means I want to know how many 'foos' with 'user_id'.

Eg:

user_id foos_count ------------- 1 31 2 52

最满意答案

以下是满足需求的查询：

Foo.group(:user_id).count

Here is the query to meet the need :

Foo.group(:user_id).count