sum of all values in column in array based on column value from other array

Question

I have an array of user info in @user_info and in array there is a column total and column user_id.

I have another instance variable @product and it has column user_id

How do i calculate sum of all values in column total verifying the user_id from @user_info and @product same?

I am trying to calcuate sum in controller, store it in instance variable and use that variable in JSON

Thanks

Ursus · Accepted Answer · 2017-03-09 16:59:38Z

1

Try something like

@user_info.select { |user_info| user_info.user_id == @product.user_id }.sum(&:total)

or, if @user_info is not a simple Array, you should be able to do in one SQL query

@user_info.where(user_id: @product.user_id).sum(:total)

answered Mar 9, 2017 at 16:53

Ursus

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1 Comment

My pleasure Sir :)