数据库中的carpool_tppe:"我要找车"，是发布信息界面选择的发布信息类型，想以这个类型对数据进行分类，显示在导航栏对应的数据中，console.log()打印出来的结果是0，没有获取到数据，如图：

wxml代码：

<segment items="{{items}}" defaultIndex="0"
binditemchanged="onSegmentItemChanged" >
  <view slot="0" class="segment-page people">
    <view class="quanbu-group">
      <view class="shu-group">|</view>
      <text>全部信息（共有500条信息）</text>
      <view class="paixu-group">按出发时间排序</view>
    </view>
    <view class="people-group" wx:for="{{carpoolings}}" wx:key="key" wx:for-item="carpooling">
      <view class="people-left">
        <view class="people-title">
          <view class="people-top">
            <text>顶</text>
          </view>
          <view class="departure-time">出发：</view>
          <view class="people-start">{{carpooling.date}}</view>
        </view>
        <view class="people-route">
          <text class="people-content">{{carpooling.departure_address}}</text>
          <text class="people-arrow">→ </text>
          <text class="purpose-content">{{carpooling.end}}</text>
          <text>（</text>
          <text class="channel-centent">{{carpooling.channel}}</text>
          <text>）</text>
        </view>
        <view class="people-seat-list">
          <view class="people-model-title">车型：</view>
          <view class="people-model">{{carpooling.vehicle_type}}</view>
          <view class="people-seat">{{carpooling.people}}空位</view>
        </view>
        <view class="people-details">
          <view class="people-remarks">备注:</view>
          <text>{{carpooling.content}}</text>
        </view>
        <view class="release-list">
          <view class="release">发布：</view>
          <view class="detail-time">2022/9/2 8:35:36</view>
        </view>
      </view>
      <view class="people-right">
        <button class="people-contact">
          <image src="/images/telephone.png"></image>
        </button>
      </view>
    </view>
  </view>
  <view slot="1" class="segment-page car"></view>
</segment>
js代码：
 onLoad: function (options) {
 
  },
  loadcarpoolings:function(){
    const that=this;
    
    db.collection("carpooling").where({
    
     carpool_type:"我要找车"
    }).limit(10).get().then(res=>{
      console.log(res);
      const carpoolings = res.data
      that.setData({
        "carpoolings":carpoolings
      })
    })
  
  },
  onSegmentItemChanged:function(event){
    // console.log(event);
    const active = event.detail.index;
    this.setData({
      active:active
    })
  
    console.log(event.detail.index);
    db.collection("carpooling").where({
      carpool_type:event.detail.index.toString()
    })
    .get({
      success:function(res){
        console.log(res);
        that.setData({
          "carpooling":res.data
        })
      }
    })
  
  },