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$shardedDataDistribution (aggregation)

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  • Definition
  • Syntax
  • Output Fields
  • Examples
$shardedDataDistribution

New in version 6.0.3.

Returns information on the distribution of data in sharded collections.

Note

This aggregation stage is only available on mongos.

This aggregation stage must be run on the admin database. The user must have the shardedDataDistribution privilege action.

The shardedDataDistribution stage has the following syntax:

db.aggregate( [
{ $shardedDataDistribution: { } }
] )

The $shardedDataDistribution stage outputs an array of documents for each sharded collection in the database. These documents contain the following fields:

Field Name
Data Type
Description
ns
string
Namespace of the sharded collection.
shards
array
Shards in the collection with the data distribution information for each shard.
shards.numOrphanedDocs
integer
Number of orphaned documents in the shard.
shards.numOwnedDocuments
integer
Number of documents owned by the shard.
shards.ownedSizeBytes
integer
Storage in bytes for documents owned by the shard.
shards.orphanedSizeBytes
integer
Storage in bytes for orphaned documents in the shard.
db.aggregate( [
{ $shardedDataDistribution: { } }
] )

Example output:

[
{
"ns": "test.names",
"shards": [
{
"shardName": "shard-1",
"numOrphanedDocs": 0,
"numOwnedDocuments": 6,
"ownedSizeBytes": 366,
"orphanedSizeBytes": 0
},
{
"shardName": "shard-2",
"numOrphanedDocs": 0,
"numOwnedDocuments": 6,
"ownedSizeBytes": 366,
"orphanedSizeBytes": 0
}
]
}
]
← $setWindowFields (aggregation)