> use newdb
switched to db newdb
> db.dropDatabase()
{ "dropped" : "newdb", "ok" : 1 }
> db.stats()
{
        "db" : "newdb",
        "collections" : 0,
        "objects" : 0,
        "avgObjSize" : 0,
        "dataSize" : 0,
        "storageSize" : 0,
        "numExtents" : 0,
        "indexes" : 0,
        "indexSize" : 0,
        "fileSize" : 0,
        "dataFileVersion" : {

        },
        "ok" : 1
}
> db.getMongo().insert('newdb.foo', {$notAllowed: true}, 0);
> db.stats()
{
        "db" : "newdb",
        "collections" : 0,
        "objects" : 0,
        "avgObjSize" : 0,
        "dataSize" : 0,
        "storageSize" : 0,
        "numExtents" : 0,
        "indexes" : 0,
        "indexSize" : 0,
        "fileSize" : 0,
        "dataFileVersion" : {

        },
        "ok" : 1
}
> db.foo.runCommand('insert', {documents: [{$notAllowed: true}]})
{
        "ok" : 1,
        "n" : 0,
        "writeErrors" : [
                {
                        "index" : 0,
                        "code" : 2,
                        "errmsg" : "Document can't have $ prefixed field names: $notAllowed"
                }
        ]
}
> db.stats()
{
        "db" : "newdb",
        "collections" : 3,
        "objects" : 4,
        "avgObjSize" : 64,
        "dataSize" : 256,
        "storageSize" : 24576,
        "numExtents" : 3,
        "indexes" : 1,
        "indexSize" : 8176,
        "fileSize" : 67108864,
        "nsSizeMB" : 16,
        "dataFileVersion" : {
                "major" : 4,
                "minor" : 5
        },
        "extentFreeList" : {
                "num" : 0,
                "totalSize" : 0
        },
        "ok" : 1
}
> db.foo.stats()
{
        "ns" : "newdb.foo",
        "count" : 0,
        "size" : 0,
        "storageSize" : 8192,
        "numExtents" : 1,
        "nindexes" : 1,
        "lastExtentSize" : 8192,
        "paddingFactor" : 1,
        "systemFlags" : 1,
        "userFlags" : 1,
        "totalIndexSize" : 8176,
        "indexSizes" : {
                "_id_" : 8176
        },
        "ok" : 1
}