MongoDB查询以更新集合中的特定文档
要进行更新，请使用$set和UPDATE。让我们创建一个包含文档的集合-
>db.demo135.insertOne({"Details":[{"EmployeeId":101,"EmployeeName":"Chris","EmployeeSalary":45000},{"EmployeeId":102,"EmployeeName":"Chris","EmployeeSalary":45000}]});
{
"acknowledged" : true,
"insertedId" : ObjectId("5e31a5ddfdf09dd6d085399c")
}在find()方法的帮助下显示集合中的所有文档-
> db.demo135.find().pretty();
这将产生以下输出-
{
"_id" : ObjectId("5e31a5ddfdf09dd6d085399c"),
"Details" : [
{
"EmployeeId" : 101,
"EmployeeName" : "Chris",
"EmployeeSalary" : 45000
},
{
"EmployeeId" : 102,
"EmployeeName" : "Chris",
"EmployeeSalary" : 45000
}
]
}以下是更新第二个文档的查询-
> db.demo135.update(
... {
...
... "Details.EmployeeId":102,
...
... },
... {
... $set: {
... "Details.$.EmployeeName" : "John Doe"
... }
... }
... );
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })在find()方法的帮助下显示集合中的所有文档-
> db.demo135.find().pretty();
这将产生以下输出-
{
"_id" : ObjectId("5e31a5ddfdf09dd6d085399c"),
"Details" : [
{
"EmployeeId" : 101,
"EmployeeName" : "Chris",
"EmployeeSalary" : 45000
},
{
"EmployeeId" : 102,
"EmployeeName" : "John Doe",
"EmployeeSalary" : 45000
}
]
}