我在查询构建器中使用连接,这是输出
[
{
"id": 7,
"name": "class 1",
"idSubject": 17,
"nameSubject": "Math"
},
{
"id": 7,
"name": "class 1",
"idSubject": 16,
"nameSubject": "history"
},
{
"id": 8,
"name": "class 2",
"idSubject": 15,
"nameSubject": "Computer"
},
{
"id": 8,
"name": "class 2",
"idSubject": 19,
"nameSubject": "geography"
}
]
您可以看到 1、2 类的 id 和名称出现了两次。那么,如何让它出现一次。
这是我的查询:
$data = DB::table('class')->join('class_subject','class.id','=','class_subject.class_id')
->join('subject','class_subject.subject_id','=','subject.id')
->select('class.id','class.name','subject.id as idSubject','subject.name as nameSubject') ->get();
我想要:
[
{
"id": 7,
"name": "class 1",
"subject": [{"idSubject":"17","nameSubject: "Math"},
{"idSubject":"16","nameSubject: "history"}]
}
]
答案 0 :(得分:0)
distinct
方法允许您强制查询返回不同的结果:
试试这个
$data = DB::table('class')->join('class_subject','class.id','=','class_subject.class_id')
->join('subject','class_subject.subject_id','=','subject.id')
->select('class.id','class.name','subject.id as idSubject','subject.name as nameSubject')->distinct()->get();