Shard a Collection
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To shard a collection, you must specify the full namespace of the
collection that you want to shard and the shard key. You can use the
mongosh method sh.shardCollection() to
shard a collection:
sh.shardCollection(<namespace>, <key>) // Optional parameters omitted
namespace | Specify the full namespace of the collection that you want to
shard ( "<database>.<collection>"). |
key | Specify a document
|
For more information on the sharding method, see
sh.shardCollection().
Shard Key Fields and Values
Missing Shard Key Fields
Documents in sharded collections can be missing the shard key fields.
A missing shard key falls into the same range as a null-valued shard key.
See Missing Shard Key Fields.
Change a Document's Shard Key Value
You can update a document's shard key value unless the shard key field is the
immutable _id field.
For details on updating the shard key value, see Change a Document's Shard Key Value.
Change a Collection's Shard Key
Starting in MongoDB 5.0, you can reshard a collection by changing a document's shard key.
You can refine a shard key by adding a suffix field or fields to the existing shard key.