MongoDB Java pull

问题

i tried to remove an embedded document without succcess. I'm looking for the java way of following instruction:

db.games.update({'_id': 73}, {$pull: {'goals': {'goal': 4}}})

回答1:

The Java documentation is pretty clear, you are just constructing BSON objects to match their respective JSON counterparts as used in the shell:

    BasicDBObject query = new BasicDBObject("_id", 73);
    BasicDBObject fields = new BasicDBObject("goals", 
        new BasicDBObject( "goal", 4));
    BasicDBObject update = new BasicDBObject("$pull",fields);

    games.update( query, update );

回答2:

Using Bson is similar.

Bson query = new Document().append("_id", 73);
Bson fields = new Document().append("goals", new Document().append( "goal", 4));
Bson update = new Document("$pull",fields);

games.updateOne( query, update );

来源：https://stackoverflow.com/questions/22875150/mongodb-java-pull