I'm trying to use MongoDB's Java driver to make two updates ($set and $push) to a record in the same operation. I'm using code similar to the following:
BasicDBObject pushUpdate = new BasicDBObject().append("$push", new BasicDBObject().append("values", dboVital));
BasicDBObject setUpdate = new BasicDBObject().append("$set", new BasicDBObject().append("endTime", time));
BasicDBList combinedUpdate = new BasicDBList();
combinedUpdate.add( pushUpdate);
combinedUpdate.add( setUpdate);
collection.update( new BasicDBObject().append("_id", pageId), combinedUpdate, true, false);
When I combine the $set and $push into the same update via a BasicDBList, I get an IllegalArgumentException: "fields stored in the db can't start with '$' (Bad Key: '$push')".
If I make two separate updates, both pushUpdate and setUpdate produce valid results.
Thanks!
2 Answers
I don't know Java driver, but do you have to create a list there? What happens if you try this code?
BasicDBObject update = new BasicDBObject().append("$push", new BasicDBObject().append("values", dboVital));
update = update.append("$set", new BasicDBObject().append("endTime", time));
collection.update( new BasicDBObject().append("_id", pageId), update, true, false);
This should produce the equivalent of
db.collection.update({_id: pageId}, {$push: {values: dboVital}, $set: {endTime: time}});
Whereas your code produces (I suspect) this:
db.collection.update({_id: pageId}, [{$push: {values: dboVital}}, {$set: {endTime: time}}]);
My mongodb version is 3.4.20 and while using
db.collection.update({_id: pageId}, [{$push: {values: dboVital}}, {$set: {endTime: time}}]);
I received error
[thread1] Error: field names cannot start with $ [$push] :
To solve that error we can use:
db.collection.update({_id: pageId}, {$push: {values: dboVital}, $set: {endTime: time}});
