Search code examples
c#.netmongodbmongodb-.net-driver

Mongo throwing "Element name 'name' is not valid' exception


I'm updating a simple field.

var filterDocument = new BsonDocument { { "name", "alice" } };

var newDocument = new BsonDocument { { "name", "Alice" } };

collection.UpdateOne(filterDocument, newDocument);

But when I reach the the update statement I get an exception {"Element name 'name' is not valid'."}

What's wrong with that element name?

Update

Re-writing it to this:

var filterDocument = new BsonDocument { { "x", "alice" } };

var newDocument = new BsonDocument { { "y", "Alice" } };

collection.UpdateOne(filterDocument, newDocument);

Throw the exception {"Element name 'y' is not valid'."}

Also, UpdateOne() or UpdateMany() makes no difference.

Also, from the shell it's fine.

> db.crud.update({name:'alice'},{name:'Alice'})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })

Solution

  • In contrast to update, updateOne seems to require an update operator;

    > db.test.updateOne({name:'alice'},{name:'Alice'})
    2016-02-16T19:04:07.689+0000 E QUERY    [thread1] Error: the update operation document must contain atomic operators
    
    > db.test.updateOne({name:'alice'},{$set: {name:'Alice'}})
    { "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 1 }
    

    ...which means your document should probably look like;

    var newDocument = 
        new BsonDocument { { "$set", new BsonDocument {"name", "Alice" } } };
    

    ...or if you really mean to replace the entire document, use replaceOne, which should work with your existing documents to replace the entire matching document.