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- MongoDB\Collection::createIndex()
MongoDB\Collection::createIndex()
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Definition
-
MongoDB\Collection::createIndex
Create an index for the collection.
This method has the following parameters:
Parameter Type Description $key
array|object Specifies the field or fields to index and the index order.
For example, the following specifies a descending index on the
username
field:$options
array Optional. An array specifying the desired options. The
$options
parameter accepts all index options that your MongoDB version supports. MongoDB includes the following options:Option Type Description commitQuorum
string|integer Optional. Specifies how many data-bearing members of a replica set, including the primary, must complete the index builds successfully before the primary marks the indexes as ready.
This option accepts the same values for the
w
field in a write concern plus"votingMembers"
, which indicates all voting data-bearing nodes.This is not supported for server versions prior to 4.4 and will result in an exception at execution time if used.
New in version 1.7.
comment
mixed Optional. Enables users to specify an arbitrary comment to help trace the operation through the database profiler, currentOp output, and logs.
This is not supported for server versions prior to 4.4 and will result in an exception at execution time if used.
New in version 1.13.
unique
boolean Optional. Creates a unique index. collation
array|object Optional. Specifies the collation for the index.
Collation allows users to specify language-specific rules for string comparison, such as rules for lettercase and accent marks. When specifying collation, the
locale
field is mandatory; all other collation fields are optional. For descriptions of the fields, see Collation Document.If the collation is unspecified but the collection has a default collation, the operation uses the collation specified for the collection. If no collation is specified for the collection or for the operation, MongoDB uses the simple binary comparison used in prior versions for string comparisons.
partialFilterExpression
array|object Optional. Creates a partial index. sparse
boolean Optional. Creates a sparse index. expireAfterSeconds
integer Optional. Creates a TTL index. maxTimeMS
integer Optional. The cumulative time limit in milliseconds for processing operations on the cursor. MongoDB aborts the operation at the earliest following interrupt point.
New in version 1.3.
name
string Optional. A name that uniquely identifies the index. By default, MongoDB creates index names based on the key. background
string Optional. Instructs MongoDB to build the index as a background process. 2dsphereIndexVersion
integer Optional. Overrides the server’s default version for a 2dsphere index. session
MongoDB\Driver\Session Optional. Client session to associate with the operation.
New in version 1.3.
writeConcern
MongoDB\Driver\WriteConcern Optional. Write concern to use for the operation. Defaults to the collection’s write concern.
It is not possible to specify a write concern for individual operations as part of a transaction. Instead, set the
writeConcern
option when starting the transaction with startTransaction.For a full list of the supported index creation options, refer to the createIndexes command reference in the MongoDB manual.
Return Values
The name of the created index as a string.
Errors/Exceptions
MongoDB\Exception\UnsupportedException
if options are used and
not supported by the selected server (e.g. collation
, readConcern
,
writeConcern
).
MongoDB\Exception\InvalidArgumentException
for errors related to
the parsing of parameters or options.
MongoDB\Driver\Exception\RuntimeException for other errors at the driver level (e.g. connection errors).
Examples
Create a Compound Index
The following example creates a compound index
on the borough
and cuisine
fields in the restaurants
collection in
the test
database.
The output would then resemble:
Create a Partial Index
The following example adds a partial index on
the borough
field in the restaurants
collection in the test
database. The partial index indexes only documents where the borough
field
exists.
The output would then resemble:
See Also
MongoDB\Collection::createIndexes()
- Indexes
- createIndexes command reference in the MongoDB manual
- Index documentation in the MongoDB Manual