Mastering MongoDB 4.x - Second Edition

Scripting for the mongo shell

Administering the database using built-in commands is helpful, but it's not the main reason for using the shell. The true power of the mongo shell comes from the fact that it is a JavaScript shell.

We can declare and assign variables in the shell as follows:

> var title = 'MongoDB in a nutshell'> titleMongoDB in a nutshell> db.books.insert({title: title, isbn: 102})WriteResult({ "nInserted" : 1 })> db.books.find(){ "_id" : ObjectId("59203874141daf984112d080"), "title" : "MongoDB in a nutshell", "isbn" : 102 }

In the previous example, we declared a new title variable as MongoDB in a nutshell and used the variable to insert a new document into our books collection, as shown in the following code.

As it's a JavaScript ...