use hospital

db.patients.inserOne({name: "Max", age: 29, diseaseSummary: "sum-max-1"})
db.patients.findOne()

    db.diseaseSummaries.inserOne({_id: "sum-max-1", diseases: ["cold", "fiever"]})

db.patients.findOne()

db.patients.findOne().diseaseSummary

var dsid = db.patients.findOne().diseaseSummary

db.diseaseSummaries.findOne({_id: dsid})