MongoDB .Net driver 2.0 Builders Filter(字段与数组比较)
MongoDB .Net driver 2.0 Builders Filter (field to array comparison)
我需要从 "followingList.username" 获取所有用户名并与
帖子的用户名,如果有任何匹配项需要将其添加到数组中。
Person Model
{
"_id" : ObjectId("554f20f5c90d3c7ed42303e1"),
"username" : "fatihyildizhan",
"followingList" : [
{
"_id" : ObjectId("55505b6ca515860cbcf7901d"),
"username" : "gumusluk",
"avatar" : "avatar.png"
},
{
"_id" : ObjectId("58505b6ca515860cbcf7901d"),
"username" : "yalikavak",
"avatar" : "avatar.png"
},
{
"_id" : ObjectId("58305b6ca515860cbcf7901d"),
"username" : "gumbet",
"avatar" : "avatar.png"
}
]
}
Post Model
{
"_id" : ObjectId("554f2df2a388R4b425b89833"),
"username" : "yalikavak",
"category" : "Summer",
"text" : "blue voyage with yacht"
},
{
"_id" : ObjectId("554f2df2a388P4b425b89833"),
"username" : "yalikavak",
"category" : "Winter",
"text" : "is coming ..."
},
{
"_id" : ObjectId("554f2df2a388K4b425b89833"),
"username" : "gumbet",
"category" : "Fall",
"text" : "there are many trees"
}
我尝试获取如下结果代码块,但无法弄清楚。
var filter = Builders<Post>.Filter.AnyEq("username", usernameList);
var result = collection.Find(filter).ToListAsync().Result;
你能帮我解决这个问题吗?
谢谢
逻辑颠倒了,如果我正确理解你的用例,你需要的是$in
query:
var filter = Builders<Post>.Filter.In("username", usernameList);
var result = collection.Find(filter).ToListAsync().Result;
在您的例子中,username
是一个简单的字段,您希望与候选人列表进行匹配。 AnyEq
用于检查嵌入的复杂对象列表中是否至少有一个符合条件。这仍然转化为 MongoDB 中的简单查询,但需要 'reach into' 需要更复杂语法的对象。
我需要从 "followingList.username" 获取所有用户名并与 帖子的用户名,如果有任何匹配项需要将其添加到数组中。
Person Model
{
"_id" : ObjectId("554f20f5c90d3c7ed42303e1"),
"username" : "fatihyildizhan",
"followingList" : [
{
"_id" : ObjectId("55505b6ca515860cbcf7901d"),
"username" : "gumusluk",
"avatar" : "avatar.png"
},
{
"_id" : ObjectId("58505b6ca515860cbcf7901d"),
"username" : "yalikavak",
"avatar" : "avatar.png"
},
{
"_id" : ObjectId("58305b6ca515860cbcf7901d"),
"username" : "gumbet",
"avatar" : "avatar.png"
}
]
}
Post Model
{
"_id" : ObjectId("554f2df2a388R4b425b89833"),
"username" : "yalikavak",
"category" : "Summer",
"text" : "blue voyage with yacht"
},
{
"_id" : ObjectId("554f2df2a388P4b425b89833"),
"username" : "yalikavak",
"category" : "Winter",
"text" : "is coming ..."
},
{
"_id" : ObjectId("554f2df2a388K4b425b89833"),
"username" : "gumbet",
"category" : "Fall",
"text" : "there are many trees"
}
我尝试获取如下结果代码块,但无法弄清楚。
var filter = Builders<Post>.Filter.AnyEq("username", usernameList);
var result = collection.Find(filter).ToListAsync().Result;
你能帮我解决这个问题吗? 谢谢
逻辑颠倒了,如果我正确理解你的用例,你需要的是$in
query:
var filter = Builders<Post>.Filter.In("username", usernameList);
var result = collection.Find(filter).ToListAsync().Result;
在您的例子中,username
是一个简单的字段,您希望与候选人列表进行匹配。 AnyEq
用于检查嵌入的复杂对象列表中是否至少有一个符合条件。这仍然转化为 MongoDB 中的简单查询,但需要 'reach into' 需要更复杂语法的对象。