Scope that has three levels deep joins

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闹比i
闹比i 2021-01-26 06:11

My Program table has many Measures My Measure table has many Targets My Target table has a column called \"

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  •  隐瞒了意图╮
    2021-01-26 06:33

    What is the target.money of a Program, the sum of all Targets.money of all Measures for this Program ?

    You can try something like:

    Target.order_by( :money => :desc ).map{|target| target.measure }.map{|measure| measure.program }.uniq
    

    Good luck

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