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Ruby on rails ActiveRecord rails 4不等于条件_Ruby On Rails_Ruby On Rails 4_Activerecord - Fatal编程技术网

Ruby on rails ActiveRecord rails 4不等于条件

Ruby on rails ActiveRecord rails 4不等于条件,ruby-on-rails,ruby-on-rails-4,activerecord,Ruby On Rails,Ruby On Rails 4,Activerecord,我正在使用rails 4开发我的应用程序。我的活动记录查询中存在不等于条件的问题。我没有得到所需的输出。我认为有一个不等于部分的问题 @available_rooms = Room.joins("LEFT OUTER JOIN reservations ON reservations.room_id = rooms.id").where("category_id = ? AND arrival_date != ?",params[:category],params[:arrival_date])

我正在使用rails 4开发我的应用程序。我的活动记录查询中存在不等于条件的问题。我没有得到所需的输出。我认为有一个不等于部分的问题

@available_rooms = Room.joins("LEFT OUTER JOIN reservations ON reservations.room_id = rooms.id").where("category_id = ? AND arrival_date != ?",params[:category],params[:arrival_date])

您可以在Rails 4中使用
where.not()

 @available_rooms = Room.joins("LEFT OUTER JOIN reservations ON reservations.room_id = rooms.id")
                        .where(category_id: params[:category])
                        .where.not(arrival_date: params[:arrival_date])

在某些版本的SQL中,notequal被写成
=

使用比较器尝试此操作,如下所示:

 @available_rooms = Room.joins("LEFT OUTER JOIN reservations ON reservations.room_id = rooms.id")
.where("category_id = ? AND arrival_date <> ?",params[:category],params[:arrival_date])
@available\u rooms=Room.joins(“在reservations.Room\u id=rooms.id上加入左侧外部预订”)
.其中(“类别id=?和到达日期?”,参数[:类别],参数[:到达日期])

对你有用吗?@Cyzanfar是的,确实有用:)