printCollectionStats() – Return statistics from all collections command

Values for the following properties are returned:

ns

The namespace of a specified collection:

"<JSON namespace>": "<name>.<collection name>"

count

Total number of rows in all collections

size

Total size of the stored documents in all collections.

aveObjSize

Average size of the stored documents, in kilobytes (KB).

numExtents

Total number of contiguously allocated data file regions.

nindexes

Number of Indexes, including the primary index.

lastExtentSize

Size of the last extent allocated.

paddingFactor

Automatically-calibrated constant for determining the amount of extra space to be allocated per document container, on disk.

systemFlags

Number of flags on the current collection.

userFlags

Number of user-set flags on the collection.

totalIndexSizes

Total size of indexes on all collections.

indexSizes

List of indexes and their sizes on all collections.

indexSizes[{"<indexname>": <size>}]

The following example shows the command syntax for returning statistics for all collections in the current database:

db.printCollectionStats()

The following example shows the syntax of a value returned from running the printCollectionStats command:

{"ns":"TEST.mycoll","count":8,"size":909312.0,"avgObjSize":111.0,
"numExtents":-1,"nindexes":1,"lastExtentSize":-1,"paddingFactor":-1,"systemFlags":-1,
"userFlags":-1,"totalIndexSizes":-1,"indexSizes":[{"_id_":-1}],"ok":1}
{"ns":"TEST.newC","count":0,"size":-1,"avgObjSize":-1.0,"numExtents":-
1,"nindexes":1,"lastExtentSize":-1,"paddingFactor":-1,"systemFlags":-
1,"userFlags":-1,"totalIndexSizes":-1,"indexSizes":[{"_id_":-
1}],"ok":1,"capped":true,"cappedsize":1000,"cappedrows":5000}