> db.stats(); {   "db" : "test",        //當(dāng)前數(shù)據(jù)庫   "collections" : 3,      //當(dāng)前數(shù)據(jù)庫多少表   "objects" : 4,        //當(dāng)前數(shù)據(jù)庫所有表多少條數(shù)據(jù)   "avgObjSize" : 51,      //每條數(shù)據(jù)的平均大小   "dataSize" : 204,      //所有數(shù)據(jù)的總大小   "storageSize" : 16384,    //所有數(shù)據(jù)占的磁盤大小   "numExtents" : 3,   "indexes" : 1,        //索引數(shù)   "indexSize" : 8176,     //索引大小   "fileSize" : 201326592,   //預(yù)分配給數(shù)據(jù)庫的文件大小   "nsSizeMB" : 16,   "dataFileVersion" : {     "major" : 4,     "minor" : 5   },   "ok" : 1 } 

> db.posts.stats(); {   "ns" : "test.posts",   "count" : 1,   "size" : 56,   "avgObjSize" : 56,   "storageSize" : 8192,   "numExtents" : 1,   "nindexes" : 1,   "lastExtentSize" : 8192,   "paddingFactor" : 1,   "systemFlags" : 1,   "userFlags" : 0,   "totalIndexSize" : 8176,   "indexSizes" : {     "_id_" : 8176   },   "ok" : 1 }