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db.collection.validate()![](/docs/v5.3/assets/link.svg)
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Description![](/docs/v5.3/assets/link.svg)
db.collection.validate(<documents>)
Important
mongosh Method
This is a
mongosh
method. This is not the documentation forNode.js
or other programming language specific driver methods.In most cases,
mongosh
methods work the same way as the legacymongo
shell methods. However, some legacy methods are unavailable inmongosh
.For the legacy
mongo
shell documentation, refer to the documentation for the corresponding MongoDB Server release:For MongoDB API drivers, refer to the language specific MongoDB driver documentation.
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.
Syntax![](/docs/v5.3/assets/link.svg)
Note
Changed in version 4.4
db.collection.validate()
no longer accepts just a boolean
parameter. See db.collection.validate() Parameter Change.
Changed in version 5.0.
The db.collection.validate()
method has the following syntax:
db.collection.validate( { full: <boolean>, // Optional repair: <boolean> // Optional, added in MongoDB 5.0 } )
Parameters![](/docs/v5.3/assets/link.svg)
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 Starting in MongoDB 3.6, for the WiredTiger storage engine, only the
In previous versions, the data validation process for the WT storage engine always forces a checkpoint. | |
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:
New in version 5.0. |
Behavior![](/docs/v5.3/assets/link.svg)
Performance![](/docs/v5.3/assets/link.svg)
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![](/docs/v5.3/assets/link.svg)
Starting in version MongoDB 4.4,
The
$currentOp
and thecurrentOp
command includedataThroughputAverage
anddataThroughputLastSecond
information for validate operations in progress.The log messages for validate operations include
dataThroughputAverage
anddataThroughputLastSecond
information.
Examples![](/docs/v5.3/assets/link.svg)
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 } )
For details of the output, see Validate Output.