Javascript 为什么update（）在发送多个对象时删除firebase中以前的子对象数据？

我的firebase结构有一个名为“playerNames”的子级。当我像这样发送数据时：

firebase.database().ref("games/" + gameId + "/playerNames/").update({[playerName]: 1});

var player = {authId: uid, joinTime: firebase.database.ServerValue.TIMESTAMP, leaveTime: "", name: playerName, status: "1", ticket1: "", ticket2: "", ticket3: "", totalTickets: totalTickets};

var data = {};
data["games/" + gameId + "/players/" + playerId] = player;
data["games/" + gameId + "/playerNames"] = {[playerName]: 1};

firebase.database().ref().update(data);

玩家名称将与值1一起追加

但当我像这样发送数据时：

firebase.database().ref("games/" + gameId + "/playerNames/").update({[playerName]: 1});

var player = {authId: uid, joinTime: firebase.database.ServerValue.TIMESTAMP, leaveTime: "", name: playerName, status: "1", ticket1: "", ticket2: "", ticket3: "", totalTickets: totalTickets};

var data = {};
data["games/" + gameId + "/players/" + playerId] = player;
data["games/" + gameId + "/playerNames"] = {[playerName]: 1};

firebase.database().ref().update(data);

播放名称中先前的数据将被覆盖

为什么会这样。我做错什么了吗？这是因为

在第一种情况下，将

{[playerName]：1}

对象传递给该方法，并将更新应用于

的“games/”+gameId+“/playerNames/”

节点

而

在第二种情况下，传递整个

数据

对象，并将更新应用于数据库的根节点（因此整个

“games/”+gameId+“/playerNames/”

节点被替换）

您需要执行以下操作：

var player = {authId: uid, joinTime: firebase.database.ServerValue.TIMESTAMP, leaveTime: "", name: playerName, status: "1", ticket1: "", ticket2: "", ticket3: "", totalTickets: totalTickets};

var data = {};
data["games/" + gameId + "/players/" + playerId] = player;
data["games/" + gameId + "/playerNames/" + playerName] = 1;

firebase.database().ref().update(data);

---

它将让“游戏/”+gameId+“/playerNames/”下的所有其他节点“不受影响”

世界需要像你这样的天才。谢谢你，先生，这很有效。