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Definition![](/docs/manual/assets/link.svg)
dataSize
The
dataSize
command returns the size in bytes for the specified data.
Syntax![](/docs/manual/assets/link.svg)
The command has the following syntax:
db.runCommand( { dataSize: <string>, keyPattern: <document>, min: <document>, max: <document>, estimate: <boolean> } )
Command Fields![](/docs/manual/assets/link.svg)
The command takes the following fields:
Field | Type | Description |
---|---|---|
dataSize | string | The name of the target collection. |
keyPattern | document | Optional. The collection's key pattern to examine. The collection must have an index with the corresponding pattern.
Otherwise |
min | document | Optional. The lower bound of the key range to be examined. |
max | document | Optional. The upper bound of the key range to be examined. |
estimate | boolean | Optional. When Defaults to false. |
Example![](/docs/manual/assets/link.svg)
The following operation runs the dataSize
command on the
database.collection
collection, specifying a key pattern of {field: 1}
with the lower bound of the range of keys to be examined being {field: 10}
and the upper bound of the key to be examined being {field: 100}
.
db.runCommand({ dataSize: "database.collection", keyPattern: { field: 1 }, min: { field: 10 }, max: { field: 100 } })
This returns a document with the size in bytes for all matching
documents. Replace database.collection
with the database and
collection from your deployment.
The amount of time required to return dataSize
depends on the
amount of data in the collection.