db.collection.createIndex()

Definition

db.collection.createIndex(keys, options, commitQuorum)

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 createIndexes command .

For MongoDB API drivers, refer to the language-specific MongoDB driver documentation .

For the legacy mongo shell documentation, refer to the documentation for the corresponding MongoDB Server release:

mongo shell v4.4

Creates indexes on collections.

To minimize the impact of building an index on replica sets and sharded clusters, use a rolling index build procedure as described on Rolling Index Builds on Replica Sets .

db.collection.createIndex() takes the following parameters:

Parameter	Type	Description
keys	document	A document that contains the field and value pairs where the field is the index key and the value describes the type of index for that field. For an ascending index on a field, specify a value of 1 ; for descending index, specify a value of -1 . An asterisk ( * ) is not a valid index name. MongoDB supports several different index types including text , geospatial , and hashed indexes. See index types for more information. Changed in version 4.2 : MongoDB 4.2 wildcard indexes support workloads where users query against custom fields or a large variety of fields in a collection: To create a wildcard index on all fields and subfields in a document, specify { "$**" : 1 } as the index key. You cannot specify a descending index key when creating a wildcard index. You can also either include or exclude specific fields and their subfields from the index using the optional wildcardProjection parameter. Wildcard indexes omit the _id field by default. To include the _id field in the wildcard index, you must explicitly include it in the wildcardProjection document: { "wildcardProjection" : { "_id" : 1, "<field>" : 0|1 } } With the exception of explicitly including _id field, you cannot combine inclusion and exclusion statements in the wildcardProjection document. You can create a wildcard index on a specific field and its subpaths by specifying the full path to that field as the index key and append "$**" to the path: { "path.to.field.$**" : 1 } You cannot specify a descending index key when creating a wildcard index. The path-specific wildcard index syntax is incompatible with the wildcardProjection option. You cannot specify additional inclusions or exclusions on the specified path. The wildcard index key must use one of the syntaxes listed above. For example, you cannot specify a compound index key . For more complete documentation on wildcard indexes, including restrictions on their creation, see Wildcard Index Restrictions . The mongod featureCompatibilityVersion must be 4.2 to create wildcard indexes. For instructions on setting the fCV, see Set Feature Compatibility Version on MongoDB 6.0 Deployments . For examples of wildcard index creation, see Create a Wildcard Index .
options	document	Optional. A document that contains a set of options that controls the creation of the index. See Options for details.
commitQuorum	integer or string	Optional. The minimum number of data-bearing voting replica set members (i.e. commit quorum), including the primary, that must report a successful index build before the primary marks the indexes as ready. A "voting" member is any replica set member where members[n].votes is greater than 0 . Supports the following values: "votingMembers" - all data-bearing voting replica set members ( Default ). "majority" - a simple majority of data-bearing voting replica set members. <int> - a specific number of data-bearing voting replica set members. 0 - Disables quorum-voting behavior. Members start the index build simultaneously but do not vote or wait for quorum before completing the index build. If you start an index build with a commit quorum of 0 , you cannot later modify the commit quorum using setIndexCommitQuorum . A replica set tag name . New in version 4.4 .

Options

The options document contains a set of options that controls the creation of the index. Different index types can have additional options specific for that type.

Multiple index options can be specified in the same document. However, if you specify multiple option documents the db.collection.createIndex() operation will fail.

Consider the following db.collection.createIndex() operation:

db.collection.createIndex(
  {
      "a": 1
  },
  {
      unique: true,
      sparse: true,
      expireAfterSeconds: 3600
  }
)

storageEngine: { <storage-engine-name>: <options> }

collation: {
   locale: <string>,
   caseLevel: <boolean>,
   caseFirst: <string>,
   strength: <int>,
   numericOrdering: <boolean>,
   alternate: <string>,
   maxVariable: <string>,
   backwards: <boolean>
}

db.myColl.createIndex( { category: 1 }, { collation: { locale: "fr" } } )

db.myColl.find( { category: "cafe" } ).collation( { locale: "fr" } )

db.myColl.find( { category: "cafe" } )

db.myColl.createIndex(
   { score: 1, price: 1, category: 1 },
   { collation: { locale: "fr" } } )

db.myColl.find( { score: 5 } ).sort( { price: 1 } )
db.myColl.find( { score: 5, price: { $gt: NumberDecimal( "10" ) } } ).sort( { price: 1 } )

db.myColl.find( { score: 5, category: "cafe" } )

wildcardProjection: {
  "path.to.field.a" : <value>,
  "path.to.field.b" : <value>
}

{
  "wildcardProjection" : {
    "_id" : 1,
    "<field>" : 0|1
  }
}

Behaviors

Examples

db.collection.createIndex( { orderDate: 1 } )

db.collection.createIndex( { orderDate: 1, zipcode: -1 } )

db.collection.createIndex( { "state" : 1, "zipcode" : "hashed" } )

db.collection.createIndex(
   { category: 1 },
   { name: "category_fr", collation: { locale: "fr", strength: 2 } }
)

db.collection.createIndex(
   { orderDate: 1, category: 1 },
   { name: "date_category_fr", collation: { locale: "fr", strength: 2 } }
)

{
  "_id" : ObjectId("5c1d358bf383fbee028aea0b"),
  "product_name" : "Blaster Gauntlet",
  "product_attributes" : {
     "price" : {
       "cost" : 299.99
       "currency" : USD
     }
     ...
  }
},
{
  "_id" : ObjectId("5c1d358bf383fbee028aea0c"),
  "product_name" : "Super Suit",
  "product_attributes" : {
     "superFlight" : true,
     "resistance" : [ "Bludgeoning", "Piercing", "Slashing" ]
     ...
  },
}

use inventory
db.products_catalog.createIndex( { "product_attributes.$**" : 1 } )

db.products_catalog.find( { "product_attributes.superFlight" : true } )
db.products_catalog.find( { "product_attributes.maxSpeed" : { $gt : 20 } } )
db.products_catalog.find( { "product_attributes.elements" : { $eq: "water" } } )

{
  "_id" : ObjectId("5c1d358bf383fbee028aea0b"),
  "product_name" : "Blaster Gauntlet",
  "product_attributes" : {
     "price" : {
       "cost" : 299.99
       "currency" : USD
     }
     ...
  }
},
{
  "_id" : ObjectId("5c1d358bf383fbee028aea0c"),
  "product_name" : "Super Suit",
  "product_attributes" : {
     "superFlight" : true,
     "resistance" : [ "Bludgeoning", "Piercing", "Slashing" ]
     ...
  },
}

use inventory
db.products_catalog.createIndex( { "$**" : 1 } )

db.products_catalog.find( { "product_price" : { $lt : 25 } } )
db.products_catalog.find( { "product_attributes.elements" : { $eq: "water" } } )

{
  "_id" : ObjectId("5c1d358bf383fbee028aea0b"),
  "product_name" : "Blaster Gauntlet",
  "product_attributes" : {
     "price" : {
       "cost" : 299.99
       "currency" : USD
     }
     ...
  }
},
{
  "_id" : ObjectId("5c1d358bf383fbee028aea0c"),
  "product_name" : "Super Suit",
  "product_attributes" : {
     "superFlight" : true,
     "resistance" : [ "Bludgeoning", "Piercing", "Slashing" ]
     ...
  },
}

use inventory
db.products_catalog.createIndex(
  { "$**" : 1 },
  {
    "wildcardProjection" : {
      "product_attributes.elements" : 1,
      "product_attributes.resistance" : 1
    }
  }
)

db.products_catalog.find( { "product_attributes.elements" : { $eq: "Water" } } )
db.products_catalog.find( { "product_attributes.resistance" : "Bludgeoning" } )

{
  "_id" : ObjectId("5c1d358bf383fbee028aea0b"),
  "product_name" : "Blaster Gauntlet",
  "product_attributes" : {
     "price" : {
       "cost" : 299.99
       "currency" : USD
     }
     ...
  }
},
{
  "_id" : ObjectId("5c1d358bf383fbee028aea0c"),
  "product_name" : "Super Suit",
  "product_attributes" : {
     "superFlight" : true,
     "resistance" : [ "Bludgeoning", "Piercing", "Slashing" ]
     ...
  },
}

use inventory
db.products_catalog.createIndex(
  { "$**" : 1 },
  {
    "wildcardProjection" : {
      "product_attributes.elements" : 0,
      "product_attributes.resistance" : 0
    }
  }
)

db.products_catalog.find( { "product_attributes.maxSpeed" : { $gt: 25 } } )
db.products_catalog.find( { "product_attributes.superStrength" : true } )

db.getSiblingDB("examples").invoices.createIndex(
  { "invoices" : 1 },
  { },
  "majority"
)