查询相关
db.getCollection('Examda_News_VisitLog').find({"newsId":"20061109480192959"})
db.getCollection('Examda_News_VisitLog').find({"from":"xcx","share":{"$gt":0}}).limit(10);
# status: "A" 为条件，item、status两个字段
ExamdaDb.collection.find( { status: "A" }, { item: 1, status: 1 } )