将所有交易总和 current_user

Question

我有一个交易模型

create_table "transactions", force: :cascade do |t|
    t.bigint "hire_id"
    t.bigint "withdraw_id"
    t.bigint "user_by_id"
    t.bigint "user_to_id"
    t.string "reference"
    t.integer "status"
    t.integer "price"
    t.integer "transaction_type"
    t.datetime "created_at", precision: 6, null: false
    t.datetime "updated_at", precision: 6, null: false
    t.index ["hire_id"], name: "index_transactions_on_hire_id"
    t.index ["user_by_id"], name: "index_transactions_on_user_by_id"
    t.index ["user_to_id"], name: "index_transactions_on_user_to_id"
    t.index ["withdraw_id"], name: "index_transactions_on_withdraw_id"
 end

Transaction_type 是一个枚举，所以我在我的事务控制器上有这个

@debit = Transaction.where(transaction_type: "Debit").sum(:price)
@credit = Transaction.where(transaction_type: "Credit").sum(:price)

我想生成 current_user 的总贷方和借方 (current_user.id==user_by_id)

请问我该怎么做？

我试过了

@total_credit_by_user = @credit.group_by(&:user_by_id).sum(:price)
@total_debit_by_user = @debit.group_by(&:user_by_id).sum(:price)

在我看来，我有

<%= @total_credit_by_user[current_user.id] %>
<%= @total_debit_by_user[current_user.id] %>

但我得到 undefined method +' for :price:Symbol`

当 current_user.id==user_by_id

时，如何通过 current_user 求和总贷方和借方

Answer 1

虽然它们看起来很相似，但 sum method for a Hash is different than the sum method for an ActiveRecord relation. Calling group_by on a relation returns a Hash object, whose sum method does not accept a column name as an argument. You can use group 相反，它将执行 GROUP BY 并允许您在 ActiveRecord 关系上使用 sum。

在这种情况下，如果您需要每个用户的总信用额度图，您可以更新控制器逻辑以将 group 与 sum 结合使用，如下所示：

credits = Transaction.where(transaction_type: "Credit")
@total_credit_by_user = credits.group(:user_by_id).sum(:price)

然后您可以通过传递他们的 ID 来访问所需用户的总积分：

@total_credit_by_user[current_user.id]

如果您只想获取当前用户的总信用额度，您可以将上述查询修改为以下内容：

@total_credit = credits.where(user_by_id: current_user.id).sum(:price)

然后就可以直接在视图中使用@total_credit值了。

将所有交易总和 current_user

Sum all transaction by current_user

ruby

ruby-on-rails

ruby-on-rails-6