例如,我在下面有一个文档,用于收集 = 交付:
{
"doc": [
{
"docid": "15",
"deliverynum": "123",
"text": "txxxxxx",
"date": "2019-07-18T12:37:58Z"
},
{
"docid": "16",
"deliverynum": "456",
"text": "txxxxxx",
"date": "2019-07-18T12:37:58Z"
},
{
"docid": "17",
"deliverynum": "999",
"text": "txxxxxx",
"date": "2019-07-18T12:37:58Z"
}
],
"id": "123",
"cancelled": false
}
是否可以使用“deliverynum”= 999 进行搜索并且输出如下所示?
{
"doc": [
{
"docid": "17",
"deliverynum": "999",
"text": "txxxxxx",
"date": "2019-07-18T12:37:58Z"
}
],
"id": "123",
"cancelled": false
}
还是我应该为 Doc 部分制作另一个 Collection?
对于这种情况,我无法在 C# 中进行查询。
最佳答案
在 Mongo shell 中,您可以使用 $(projection)运算符(operator):
db.collection.find({ "doc.deliverynum": "999" }, { "doc.$": 1 })
相应的 C# 代码如下所示:
var q = Builders<Model>.Filter.ElemMatch(x => x.doc, d => d.deliverynum == "999");
var p = Builders<Model>.Projection.ElemMatch(x => x.doc, d => d.deliverynum == "999");
var data = Col.Find(q).Project(p).ToList();
您还可以使用 q = Builders<Model>.Filter.Empty
如果您想获取所有文档,即使不包含 deliverynum =``999
关于c# - 查询 documentdb 中的子字段,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/57096251/