MongoDB查询以将文档数组中的每个元素与条件匹配？
您可以every()在MongoDB中使用它。让我们创建一个包含文档的集合-
> db.arrayConditionDemo.insertOne({"Name":"John","Marks":[40,43,45]});
{
"acknowledged" : true,
"insertedId" : ObjectId("5cbdbd06de8cc557214c0e1a")
}
> db.arrayConditionDemo.insertOne({"Name":"Mike","Marks":[45]});
{
"acknowledged" : true,
"insertedId" : ObjectId("5cbdbd17de8cc557214c0e1b")
}
> db.arrayConditionDemo.insertOne({"Name":"Chris","Marks":[43,45,59,69,78,89]});
{
"acknowledged" : true,
"insertedId" : ObjectId("5cbdbd3cde8cc557214c0e1c")
}在find()method的帮助下显示集合中的所有文档。查询如下-
> db.arrayConditionDemo.find().pretty();
这将产生以下输出-
{
"_id" : ObjectId("5cbdbd06de8cc557214c0e1a"),
"Name" : "John",
"Marks" : [
40,
43,
45
]
}
{
"_id" : ObjectId("5cbdbd17de8cc557214c0e1b"),
"Name" : "Mike",
"Marks" : [
45
]
}
{
"_id" : ObjectId("5cbdbd3cde8cc557214c0e1c"),
"Name" : "Chris",
"Marks" : [
43,
45,
59,
69,
78,
89
]
}以下是将文档数组中的每个元素与条件匹配的查询-
> db.arrayConditionDemo.find("return this.Marks.every(function(m) { return (m >= 40 && m<= 100) })");这将产生以下输出-
{ "_id" : ObjectId("5cbdbd06de8cc557214c0e1a"), "Name" : "John", "Marks" : [ 40, 43, 45 ] }
{ "_id" : ObjectId("5cbdbd17de8cc557214c0e1b"), "Name" : "Mike", "Marks" : [ 45 ] }
{ "_id" : ObjectId("5cbdbd3cde8cc557214c0e1c"), "Name" : "Chris", "Marks" : [ 43, 45, 59, 69, 78, 89 ] }