javascript - 无法从数据库获取数据

Question

我正在尝试使用真/假条件从 mongoDB 获取一些数据

这是回调函数:

module.exports.getAllTeachersByValidation = function (condition, fields, options, callback){
    const query =  {
      account: {
          valid: condition
      }
    };
    Teacher.find(query, fields, options, callback);
};

这是方案:

const teacherSchema = mongoose.Schema({
    account: {
        username: {
            type: String,
            required: true,
            unique: true,
            lowercase: true
        },
        password: {
            type: String,
            required: true
        },
        valid: {
            type: String,
            enum: ["true","false"],
            required: true,
            lowercase: true
        }
    },

代码:

const condition = req.query.condition;
    const ret_values = "_id "
            + "ID "
            + "account.username "
            + "account.valid "
            + "name "
            + "communication.email "
            + "communication.phone";
    if(typeof condition !== 'undefined'){
        console.log("Sending teachers by validation: " + condition);
        Teacher.getAllTeachersByValidation(condition.toLowerCase(), ret_values, {}, (error, teachers) => {
            if (error) throw error;
            if(teachers){
                return res.json({
                    success: true,
                    teachers
                });
            }else{
                return res.json({
                    success: false,
                    msg: "Error retrieving teachers",
                    error: "No teacher to be found"
                });
            }
        });
    }

我尝试过当 valid 为 String 类型和当 valid 为 Boolean 类型时，但结果总是得到一个空的教师数组(成功:true)

有人可以解释一下为什么 .find() 不返回数组吗？或者我的问题出在哪里？

当我不使用条件字段时，它会返回所有教师(包括当 valid 为 false/true 时)

Answer 1

在这种情况下您的查询不正确

而不是:

const query =  {
      account: {
          valid: condition
      }
};

用途:

const query =  {
      "account.valid": condition
};

在第一种情况下，您仅查询帐户子文档恰好为{"valid": "true"}的文档，而没有用户名和密码。

更多信息请点击:https://docs.mongodb.com/manual/tutorial/query-embedded-documents/