MongoDB：结合AND和OR？
首先让我们创建一个包含文档的集合-
> db.demo293.insertOne({FirstName:"Chris",LastName:"Brown",Age:24});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e4d45075d93261e4bc9ea32")
}
> db.demo293.insertOne({FirstName:"David",LastName:"Miller",Age:23});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e4d45265d93261e4bc9ea33")
}
> db.demo293.insertOne({FirstName:"John",LastName:"Smith",Age:24});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e4d45385d93261e4bc9ea34")
}
> db.demo293.insertOne({FirstName:"Adam",LastName:"Doe",Age:21});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e4d46cf5d93261e4bc9ea35")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo293.find();
这将产生以下输出-
{ "_id" : ObjectId("5e4d45075d93261e4bc9ea32"), "FirstName" : "Chris", "LastName" : "Brown", "Age" : 24 }
{ "_id" : ObjectId("5e4d45265d93261e4bc9ea33"), "FirstName" : "David", "LastName" : "Miller", "Age" : 23 }
{ "_id" : ObjectId("5e4d45385d93261e4bc9ea34"), "FirstName" : "John", "LastName" : "Smith", "Age" : 24 }
{ "_id" : ObjectId("5e4d46cf5d93261e4bc9ea35"), "FirstName" : "Adam", "LastName" : "Doe", "Age" : 21 }以下是结合AND和OR的查询-
> db.demo293.find( {
... $and : [
... {
... $or : [
... {"FirstName" : "John"},
... {"LastName" : "Brown"}
... ]
... },
... {
... Age:24
... }
... ]
...} )这将产生以下输出-
{ "_id" : ObjectId("5e4d45075d93261e4bc9ea32"), "FirstName" : "Chris", "LastName" : "Brown", "Age" : 24 }
{ "_id" : ObjectId("5e4d45385d93261e4bc9ea34"), "FirstName" : "John", "LastName" : "Smith", "Age" : 24 }