I\'m trying to explain a mongoDB update; but nothing is happening? Does Mongo not support this?
> db.movies.update({\"actors.name\": \"Christian Bale\"},
Why do you want to call explain on update? AFAIK, explain will show you how your query will fetch the rows, so you could simply do:
db.movies.find( {$query: {"actors.name": "Christian Bale"}}, {$explain: 1} );