Delete sub items from container

delete_sub_items.js

var lookup = 'http://pressassociation.com/brands/1166';

var i=0;
var container = db.content.findOne({lookup: lookup});
print('container currently has '+container.contents.length+' items.');

for (i=0; i<container.contents.length; i++) {
    if (container.contents[i] != null && container.contents[i].specialization == 'film') {
        print('removing episode at poisition '+i+': '+container.contents[i]._id+' - '+container.contents[i].title);
        //eval('db.content.update({_id: container._id}, {$unset: {"contents.'+i+'": 1 }})');
    }
}
db.content.update({_id: container._id},  {$pull : {"contents"   : null }});

var container = db.content.findOne({lookup: lookup});
print('container now has '+container.contents.length+' items.');