Quick MongoDB commands

Create mongo database:
 use <database_name>

Create Collections
db.createCollection(name, options) 

db.collection.createIndex({"key":1},{unique:true})

db.collection.deleteMany({}) to delete all items

db.collection.drop() delete collection

Insert if not found otherwise update

db.people.update(
   { name: "Andy" },
   {
      name: "Andy",
      rating: 1,
      score: 1
   },
   { upsert: true }
)