text: const mongoose = require('mongoose');
  var Schema = mongoose.Schema;
  var ObjectId = Schema.Types.ObjectId;
  
  var ClientSchema = new Schema({
    name: String,
    tel: Number,
    mail: String,
    address: String,
    info: String,
    createAt:{
      type: Date,
      default: Date.now()
    }
  })
  
  ClientSchema.statics = {
    fetch: function(cb) {
      return this
        .find({})
        .sort({'meta.creatAt':-1})         // _id 中包含了事件的算法
        .exec(cb)
    },
  
  }
  
  module.exports = ClientSchema
  