sh.moveChunk()
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Definition
sh.moveChunk(namespace, query, destination)
Moves the chunk that contains the document specified by the
query
to thedestination
shard.sh.moveChunk()
provides a wrapper around themoveChunk
database command.Important
In most circumstances, allow the balancer to automatically migrate chunks, and avoid calling
sh.moveChunk()
directly.Warning
This command cannot be used for hashed shard keys, as it uses the
find
option from themoveChunk
command. To move a chunk with a hashed shard key, use themoveChunk
command specifying thebounds
field.Important
mongosh Method
This page documents a
mongosh
method. This is not the documentation for database commands or language-specific drivers, such as Node.js.For the database command, see the
moveChunk
command.For MongoDB API drivers, refer to the language-specific MongoDB driver documentation.
sh.moveChunk()
takes the following arguments:ParameterTypeDescriptionnamespace
stringThe namespace of the sharded collection that contains the chunk to migrate.query
documentAn equality match on the shard key that selects the chunk to move.destination
stringThe name of the shard to move.By default, MongoDB cannot move a chunk if the number of documents in the chunk is greater than 2 times the result of dividing the configured chunk size by the average document size. The
moveChunk
command can specify the forceJumbo option to allow for the manual migration of chunks too large to move, with or without the jumbo label. See moveChunk command for details.
Compatibility
This method is available in deployments hosted in the following environments:
MongoDB Atlas: The fully managed service for MongoDB deployments in the cloud
Important
This command is not supported in serverless instances. For more information, see Unsupported Commands.
MongoDB Enterprise: The subscription-based, self-managed version of MongoDB
MongoDB Community: The source-available, free-to-use, and self-managed version of MongoDB
Example
Given the people
collection in the records
database, the
following operation finds the chunk that contains the documents with the
zipcode
field set to 53187
and then moves that chunk to the
shard named shard0019
:
sh.moveChunk("records.people", { zipcode: "53187" }, "shard0019")