摘要：1 var rs = db.fs.files.aggregate([ 2 {$group: {_id: '$metadata.cas', count: {$sum: 1}}}, 3 {$match: {count: {$gt: 1}}} 4 ]) 5 6 //print(rs); 7 for(var i in rs.result){ 8 var coun... 阅读全文