在模型上按其引用模型的字段进行猫鼬嵌套查询

在模型上按其引用模型的字段进行猫鼬嵌套查询

您无法在单个查询中执行此 *** 作，因为MongoDB不支持联接。相反，您必须将其分为几个步骤：

// Get the _ids of people with the last name of Robertson.Person.find({lastname: 'Robertson'}, {_id: 1}, function(err, docs) {    // Map the docs into an array of just the _ids    var ids = docs.map(function(doc) { return doc._id; });    // Get the companies whose founders are in that set.    Company.find({founder: {$in: ids}}, function(err, docs) {        // docs contains your answer    });});