db.collection.validate()
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MongoDB with drivers
This page documents a mongosh
method. To see the equivalent
method in a MongoDB driver, see the corresponding page for your
programming language:
Description
Changed in version 6.2.
db.collection.validate(<documents>)
Validates a collection. The method scans a collection data and indexes for correctness and returns the result. For details of the output, see Validate Output.
Starting in version 5.0, the
db.collection.validate()
method can also fix inconsistencies in the collection.Index inconsistencies include:
An index is multikey but there are no multikey fields.
An index has multikeyPaths covering fields that are not multikey.
An index does not have multikeyPaths but there are multikey documents (for indexes built before 3.4).
If any inconsistencies are detected by the
db.collection.validate()
command, a warning is returned and the repair flag on the index is set totrue
.db.collection.validate()
also validates any documents that violate the collection's schema validation rules.The
db.collection.validate()
method is a wrapper around thevalidate
command.
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 M0, M2, and M5 clusters or 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
Syntax
The db.collection.validate()
method has the following syntax:
db.collection.validate( { full: <boolean>, // Optional repair: <boolean>, // Optional, added in MongoDB 5.0 checkBSONConformance: <boolean> // Optional, added in MongoDB 6.2 } )
Parameters
The db.collection.validate()
method can take the
following optional document parameter with the fields:
Field | Type | Description |
---|---|---|
boolean | Optional. A flag that determines whether the command performs a slower but more thorough check or a faster but less thorough check.
The default is For the WiredTiger storage engine, only the | |
boolean | Optional. A flag that determines whether the command performs a repair.
The default is A repair can only be run on a standalone node. The repair fixes these issues:
For more information, see the New in version 5.0. | |
boolean | Optional. If
New in version 6.2. |
Behavior
Performance
The db.collection.validate()
method is potentially resource
intensive and may impact the performance of your MongoDB instance,
particularly on larger data sets.
The db.collection.validate()
method obtains an exclusive lock
on the collection. This will block all reads and writes on the
collection until the operation finishes. When run on a secondary, the
operation can block all other operations on that secondary until it
finishes.
Warning
Validation has exclusive lock requirements that affect performance
on primaries and on secondaries that are servicing reads. Consider
only running db.collection.validate()
on nodes that are
not servicing reads or writes.
To minimize impact on the primary, the majority of the data-bearing (non-arbiter), voting members in the cluster must be available and must not have significant replication lag.
To minimize the impact of the validation operation on client
applications, run db.collection.validate()
on a secondary
node that is not servicing read requests. You can convert the
current primary node to a secondary node, by running the
rs.stepDown()
method.
To completely isolate the db.collection.validate()
operation from client traffic, choose one of the following options:
Isolate a replica set member by following the rolling maintenance procedure to temporarily remove it from the cluster.
Convert a secondary node to a replica set hidden member and perform the validation on the hidden node.
Data Throughput Metrics
The $currentOp
and the currentOp
command
include dataThroughputAverage
and
dataThroughputLastSecond
information for
validate operations in progress.
The log messages for validate operations include
dataThroughputAverage
and dataThroughputLastSecond
information.
Collection Validation Improvements
Starting in MongoDB 6.2, the validate
command and
db.collection.validate()
method:
Check collections to ensure the BSON documents conform to the BSON specifications.
Check time series collections for internal data inconsistencies.
Have a new option
checkBSONConformance
that enables comprehensive BSON checks.
Examples
To validate a collection
myCollection
using the default validation setting (specifically, full: false):db.myCollection.validate() db.myCollection.validate({ }) db.myCollection.validate( { full: false } ) To perform a full validation of collection
myCollection
, specify full: true:db.myCollection.validate( { full: true } ) To repair collection
myCollection
, specify repair: true:db.myCollection.validate( { repair: true } ) To perform additional BSON conformance checks in
myCollection
, specify checkBSONConformance: true:db.myCollection.validate( { checkBSONConformance: true } )
For details of the output, see Validate Output.