lzq123_1的专栏

1.查找并且倒排序，限制显示30条 db.getCollection('cars').find({'title':/appy/,'parentCard':0},{'title':1}).sort({'searchWeight':-1,'collectCount':-1,'createdAt':-1}).limit(30) 2.查找以year开头的记录 db.getCollection('ca