使用MongoDB OR运算符选择多个值
首先让我们创建一个包含文档的集合-
> db.demo270.insertOne({"ClientName":"Chirs","Age":34});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e481e371627c0c63e7dbab8")
}
> db.demo270.insertOne({"ClientName":"David","Age":31});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e481e3d1627c0c63e7dbab9")
}
> db.demo270.insertOne({"ClientName":"Bob","Age":31});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e481e431627c0c63e7dbaba")
}
> db.demo270.insertOne({"ClientName":"Carol","Age":36});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e481e491627c0c63e7dbabb")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo270.find();
这将产生以下输出-
{ "_id" : ObjectId("5e481e371627c0c63e7dbab8"), "ClientName" : "Chirs", "Age" : 34 }
{ "_id" : ObjectId("5e481e3d1627c0c63e7dbab9"), "ClientName" : "David", "Age" : 31 }
{ "_id" : ObjectId("5e481e431627c0c63e7dbaba"), "ClientName" : "Bob", "Age" : 31 }
{ "_id" : ObjectId("5e481e491627c0c63e7dbabb"), "ClientName" : "Carol", "Age" : 36 }以下是使用OR运算符选择多个值的查询-
> db.demo270.find({
... "$or" : [
... {
... "ClientName" : "Carol"
... },
... {
... "Age" : 31
... }
... ]
...}
...);这将产生以下输出-
{ "_id" : ObjectId("5e481e3d1627c0c63e7dbab9"), "ClientName" : "David", "Age" : 31 }
{ "_id" : ObjectId("5e481e431627c0c63e7dbaba"), "ClientName" : "Bob", "Age" : 31 }
{ "_id" : ObjectId("5e481e491627c0c63e7dbabb"), "ClientName" : "Carol", "Age" : 36 }