Activerecord：查找表中的第n行

Question

{ topic: "Foo", opportunity: Opportunity.limit(15)[0] },
{ topic: "Foo", opportunity: Opportunity.limit(15)[2] },
{ topic: "Foo", opportunity: Opportunity.limit(15)[7] },
{ topic: "Foo", opportunity: Opportunity.limit(15)[9] },
{ topic: "Foo", opportunity: Opportunity.limit(15)[11]}

Opportunity.limit(15)[n]Active Record 不提供任何便利功能吗？

Answer 1

您正在寻找offset.

另请注意，不将 an 传递order给查询并不能保证查询将返回按主键排序的实例。所以最好传递一个显式的order.

Opportunity.order(:id).limit(1).offset(2)