Database Manual / Sharding / Reference / Inconsistency Types

MissingShardKeyIndex

Description

MissingShardKeyIndex

A sharded collection exists that doesn't have an index compatible with the collection shard key.

New in version 7.0.

Format

{
   type: "MissingShardKeyIndex",
   description: "<string>",
   details: {
      namespace: "<string>",
      shard: "<string>",
      shardKey: { <document> }
   }
}

MissingShardKeyIndex inconsistency documents contain the following fields:

FieldTypeDescription

type

string

Type of inconsistency document. Returns a value of MissingShardKeyIndex for this inconsistency type.

description

string

Describes the inconsistency found in the metadata.

details

document

Document with additional information on where the inconsistency exists in the database and sharded cluster.

details.namespace

string

Indicates the database and collection where the inconsistency exists.

details.shard

string

The shard where the inconsistency exists.

details.shardKey

document

The shard key that requires an index.

Example

Use the db.adminCommand() method to call the checkMetadataConsistency command:

db.adminCommand( { checkMetadataConsistency: 1 } )

The method returns a cursor with a batch of documents showing the inconsistencies found in the sharding metadata. The example below shows a cursor with a MissingShardKeyIndex inconsistency document:

{
   cursor: {
      id: Long("0"),
      ns: "test.$cmd.aggregate",
      firstBatch: [
         {
            type: "MissingShardKeyIndex",
            description: "Found sharded collection without a shard key index",
            details: {
               namespace: "test.authors",
               shard: "shard-rs0",
               shardKey: {
                  skey: 1
               }
            }
         }
      ],
   },
   ok: 1
}