update field in mongodb code example

Example 1: mongodb update field inside array

Consider the following document in the students collection whose grades element value is an array of embedded documents:

{
  _id: 4,
  grades: [
     { grade: 80, mean: 75, std: 8 },
     { grade: 85, mean: 90, std: 5 },
     { grade: 85, mean: 85, std: 8 }
  ]
}

Use the positional $ operator to update the std field of the first array element that matches the grade equal to 85 condition:

IMPORTANT
---------
You must include the array field as part of the query document.

db.students.updateOne(
   { _id: 4, "grades.grade": 85 },
   { $set: { "grades.$.std" : 6 } }
)
After the operation, the document has the following updated values:

{
   "_id" : 4,
   "grades" : [
      { "grade" : 80, "mean" : 75, "std" : 8 },
      { "grade" : 85, "mean" : 90, "std" : 6 },
      { "grade" : 85, "mean" : 85, "std" : 8 }
   ]
}

Example 2: mongodb update a data in database

db.Employee.update(
{"Employeeid" : 1},
{$set: { "EmployeeName" : "NewMartin"}});

Example 3: mongodb update

db.collectionName.update({"aField":"vale1"},{$set:{"anotherField":"value2"}})

-search for documentations for more examples than search
-aField is used to find the documents
-anotherField is the field that will be updated
-You can also use the below:
-- updateOne
-- findOneAndUpdate