javascript - Mongodb查找查询数组以元素开头

Question

我收集了如下文档:

{ "_id" : 1, "path" : [ 3, 1 ], "name" : "A" }
{ "_id" : 2, "path" : [ 3, 1, 1 ], "name" : "B" }
{ "_id" : 3, "path" : [ 3, 1, 1, 1 ], "name" : "C" }
{ "_id" : 4, "path" : [ 3, 1, 2 ], "name" : "D" }
{ "_id" : 5, "path" : [ 3, 1, 2, 1 ], "name" : "E" }
{ "_id" : 6, "path" : [ 3, 1, 3 ], "name" : "F" }
{ "_id" : 7, "path" : [ 3, 2 ], "name" : "G" }
{ "_id" : 8, "path" : [ 3, 2,1 ], "name" : "H" }

现在我正在尝试查询所有以 3,1 开头的路径:

db.exp3.find({"path": {"$elemMatch": {"0": 3}}});

不工作。

有什么提示吗？

Answer 1

您可以按如下方式查询:

db.myObject.find({"path.0" : 3, "path.1" : 1})