我正在使用ActiveRecord，在那里我试图查询课程模型。每门课程都有以下模式：
Courses:
[{
name: "Intro to Math",
id: 1,
segments: [{id: 1, subject_id: "123-456"}, {id: 1, subject_id: "789-145"}]
},
{
name: "Intro to Probability",
id: 2,
segments: [{id: 1, subject_id: "123-456"}, {id: 1, subject_id: "000-000"}]
},
{
name: "Intro to Stats",
id: 3,
segments: [{id: 1, subject_id: "111-111"}, {id: 1, subject_id: "000-000"}]
}]
我该如何编写一个ActiveRecord查询，以获取每个具有id为"123-456"的段的课程(在本例中，它将是id为1&2的课程(？
Course.joins(:segments).where(segments: { subject_id: "123-456" })
有关更多信息和示例，请参阅文档。
根据这句话：Course which has a segment which has the id "123-456" (which in this case, would be the Course with the id 1 & 2)，你的意思似乎是Course which has a segment which has the segment_id "123-456"如果是这样的话：
Courses.joins(:segments).where("segments.subject_id='123-456'")