Correction exercice 4
db.inventory.find(
{ level: { $exists: true } },
{ society: 1, level: 1, _id: 0 }
);
db.inventory.updateMany(
{ level: { $exists: true } },
{ $unset: { level: "" } }
);
db.inventory.find(
{ level: { $exists: true } }
);
17 June 2025