在Firestore中，有集合cities，posts和users。 posts的文档引用了一个user和一个city，我想从所有帖子中检索所有数据并编写查询：
firestore.collection('posts')
.get()
.then(snapshot => {
snapshot.docs.forEach(post => {
console.log(post.data())
});
});
尽管帖子中只有一个文档，但是在控制台中我却获得了数千行数据，我所需要的只是这样：
postId: {
city: "city_name",
user: {
name: "Name",
lastName: "Last"
},
description: "bla bla"
}
如何仅获取所需的数据而没有所有额外的元数据？ 这是大约30％的输出：
<code>
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</code>
答案 0 :(得分：0)
使用文档get（），您无法过滤（减少）其中的字段。使用移动和Web客户端SDK时，对于所有匹配的文档，所有字段的 all get（）操作将返回。如果您需要较少的数据，则必须将数据拆分为不同的文档，然后分别进行查询。