我怎么参考，并改变了一个额外的价值有许多通过模型 [英] how do I reference and change an extra value in a has many through model

问题描述

我得piece_lineup模型加入阵容和连身款（有许多通过）。我添加了一个状态列到piece_lineup模型，但我无法弄清楚如何引用属性和/或改变它。当列出了阵容相关的作品，我也希望，因为它涉及到阵容列出片状态。我该怎么办呢？

I have Lineup and Piece models joined by piece_lineup model (has many through). I added a 'status' column to the piece_lineup model but i can't figure out how to reference that attribute and/or change it. When listing the pieces associated with a lineup, I also want to list the status of the piece as it relates to the lineup. How do I do that?

推荐答案

这很简单，让此列。添加到您的模型：

It's very simple to get this column. Add to your model:

has_many :pieces, through: :piece_lineup, select: "pieces.*, piece_lineup.status as status"

如果您需要更改此值，则应该创建阵容＃status_for_pi​​ece =（片，状态）（为例）的方法。查找所需的行和更新状态。

If you have to change this value, you should create Lineup#status_for_piece=(piece, status) (as example) method. Find necessary row and update status.

插入不优雅的方式，但连接表是不是经常更新数据的好地方，在所有

Inserting is not elegant way, but join table is not a good place for frequently updated data at all

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