When using the $
positional operator in an update, your query needs to include a term that matches the element of the array you're updating:
db.Runtime.findAndModify({
query: {_id: ObjectId("52bb21bc8a2ebdc01c000001"),
'features.20': {$exists: true}},
update: {$set: {"features.$.20":"Updated Description"}}
})
Note that you also need to call ObjectId
on your _id
string to turn it into an actual ObjectId
or it won't match the doc.