How to use Insert in MongDB:s Function - mongodb

Question

Goal: use MongoDB's function to add new row by using function.
It is similar concept to add a new row by using a stored procedure in SQL Server.
Problem: the code doesn't work and what part am I missing?
{
"message" : "db.Test.myAddFunction is not a function",
"stack" : "script:1:10"
}
Info: I'm new to MongoDB
db.createCollection("Test")
db.inventory.insertMany([
{ item: "journal", qty: 25, tags: ["blank", "red"], size: { h: 14, w: 21, uom: "cm" } },
{ item: "mat", qty: 85, tags: ["gray"], size: { h: 27.9, w: 35.5, uom: "cm" } },
{ item: "mousepad", qty: 25, tags: ["gel", "blue"], size: { h: 19, w: 22.85, uom: "cm" } }
])
db.system.js.save(
{
_id : "myAddFunction" ,
value : function (x, y)
{
db.inventory.insertOne(
{ item: "canvas", qty: 100, tags: ["cotton"], size: { h: 28, w: 35.5, uom: "cm" } }
)
return x + y;
}
}
);
db.loadServerScripts();
db.Test.myAddFunction(2, 2);

Answer 1

You cannot.
Once you save a function in the system.js collection, you can use the function from any JavaScript context; e.g. $where operator, mapReduce command or db.collection.mapReduce().
Source: https://docs.mongodb.com/manual/tutorial/store-javascript-function-on-server/