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mongoexport

Synopsis

mongoexport is a command-line tool that produces a JSON or CSV export of data stored in a MongoDB instance.

Run mongoexport from the system command line, not the mongo shell.

See also

mongoimport which provides the corresponding structured data import capability.

Note

If you are archiving stale data to save on storage costs, consider Online Archive in MongoDB Atlas. Online Archive automatically archives infrequently accessed data to fully-managed S3 buckets for cost-effective data tiering.

Versioning

Starting with MongoDB 4.4, mongoexport is now released separately from the MongoDB Server and uses its own versioning, with an initial version of 100.0.0. Previously, mongoexport was released alongside the MongoDB Server and used matching versioning.

For documentation on the MongoDB 4.2 or earlier versions of mongoexport, reference the MongoDB Server Documentation for that version of the tool:

This documentation is for version 100.2.1 of mongoexport.

Compatibility

MongoDB Server Compatibility

mongoexport version 100.2.1 supports the following versions of the MongoDB Server:

  • MongoDB 4.4
  • MongoDB 4.2
  • MongoDB 4.0
  • MongoDB 3.6

While mongoexport may work on earlier versions of MongoDB server, any such compatibility is not guaranteed.

Platform Support

mongoexport version 100.2.1 is supported on the following platforms:

  x86_64 ARM64 PPC64LE s390x
Amazon 2      
Amazon 2013.03+      
Debian 10      
Debian 9      
Debian 8      
RHEL / CentOS 8    
RHEL / CentOS 7  
RHEL / CentOS 6    
SUSE 15      
SUSE 12    
Ubuntu 20.04    
Ubuntu 18.04
Ubuntu 16.04
Ubuntu 14.04      
Windows 8 and later      
Windows Server 2012 and later      
macOS 10.12 or later      

Installation

The mongoexport tool is part of the MongoDB Database Tools package:

Syntax

The mongoexport command has the following form:

mongoexport --collection=<coll> <options> <connection-string>

Run mongoexport from the system command line, not the mongo shell.

You must specify the collection to export. If you do not specify an output file, mongoexport writes to the standard output (e.g. stdout).

Connect to a MongoDB Instance

To connect to a local MongoDB instance running on port 27017, you do not have to specify the host or port.

For example, to export the specified collection to the specified output file from a local MongoDB instance running on port 27017:

mongoexport --collection=events --db=reporting --out=events.json

To specify a host and/or port of the MongoDB instance, you can either:

  • Specify the hostname and port in the --uri connection string:

    mongoexport --uri="mongodb://mongodb0.example.com:27017/reporting"  --collection=events  --out=events.json [additional options]
    

    When using the --uri connection string, the database can be specified as part of the string.

  • Specify the hostname and port in the --host:

    mongoexport --host="mongodb0.example.com:27017" --collection=events --db=reporting --out=events.json [additional options]
    
  • Specify the hostname and port in the --host and --port:

    mongoexport --host="mongodb0.example.com" --port=27017 --collection=events --db=reporting --out=events.json [additional options]
    

For more information on the options available, see Options.

Connect to a Replica Set

To connect to a replica set to export its data, you can either:

  • Specify the replica set name and members in the --uri connection string:

    mongoexport --uri="mongodb://mongodb0.example.com:27017,mongodb1.example.com:27017,mongodb2.example.com:27017/reporting?replicaSet=myReplicaSetName" --collection=events --out=events.json [additional options]
    

    When using the --uri connection string, the database can be specified as part of the string.

  • Specify the replica set name and members in the --host:

    mongoexport --host="myReplicaSetName/mongodb0.example.com:27017,mongodb1.example.com:27017,mongodb2.example.com" --collection=events --db=reporting --out=events.json [additional options]
    

By default, mongoexport reads from the primary of the replica set. To override the default, you can specify the read preference:

  • You can specify the read preference in the --uri connection string

    mongoexport --uri="mongodb://mongodb0.example.com:27017,mongodb1.example.com:27017,mongodb2.example.com:27017/reporting?replicaSet=myReplicaSetName&readPreference=secondary" --collection=events --out=events.json [additional options]
    

    If specifying the read preference tags, include the readPreferenceTags option:

    mongoexport --uri="mongodb://mongodb0.example.com:27017,mongodb1.example.com:27017,mongodb2.example.com:27017/reporting?replicaSet=myReplicaSetName&readPreference=secondary&readPreferenceTags=region:east" --collection=events --out=events.json [additional options]
    

    When using the --uri connection string, the database can be specified as part of the string.

  • You can specify the read preference using the --readPreference command-line option. The command-line option takes a string if specifying only the read preference mode:

    mongoexport --host="myReplicaSetName/mongodb0.example.com:27017,mongodb1.example.com:27017,mongodb2.example.com:27017" --readPreference=secondary --collection=events --db=reporting --out=events.json [additional options]
    

    Or, the command-line option can takes a quote-enclosed document '{ mode: <mode>, tagSets: [ <tag1>, ... ], maxStalenessSeconds:<num>}' to specify the mode, the optional read preference tag sets, and the optional maxStalenessSeconds:

    mongoexport --host="myReplicaSetName/mongodb0.example.com:27017,mongodb1.example.com:27017,mongodb2.example.com:27017" --readPreference='{mode: "secondary", tagSets: [ { "region": "east" } ]}' --collection=events --db=reporting --out=events.json [additional options]
    

For more information on the options available, see Options.

Connect to a Sharded Cluster

To connect to a sharded cluster to export its data, you can either:

  • Specify the hostname of the mongos instance in the --uri connection string

    mongoexport --uri="mongodb://mongos0.example.com:27017/reporting" --collection=events --out=events.json [additional options]
    

    When using the --uri connection string, the database can be specified as part of the string.

  • Specify the hostname and port of the mongos instance in the --host

    mongoexport --host="mongos0.example.com:27017" --collection=events --db=reporting --out=events.json[additional options]
    

By default, mongoexport reads from the primary of the shard replica set. To override the default, you can specify the read preference:

  • You can specify the read preference in the --uri connection string

    mongoexport --uri="mongodb://mongos0.example.com:27017/reporting?readPreference=secondary" --collection=events --out=events.json [additional options]
    

    If specifying the read preference tags, include the readPreferenceTags option:

    mongoexport --uri="mongodb://mongos0.example.com:27017/reporting?readPreference=secondary&readPreferenceTags=region:east" --collection=events --out=events.json [additional options]
    

    When using the --uri connection string, the database can be specified as part of the string.

  • You can specify the read preference using the --readPreference command-line option. The command-line option takes a string if specifying only the read preference mode:

    mongoexport --host="mongos0.example.com:27017" --readPreference=secondary --collection=events --db=reporting --out=events.json [additional options]
    

    Or, the command-line option can takes a quote-enclosed document '{ mode: <mode>, tagSets: [ <tag1>, ... ], maxStalenessSeconds:<num>}' to specify the mode, the optional read preference tag sets, and the optional maxStalenessSeconds:

    mongoexport --host="mongos0.example.com:27017" --readPreference='{mode: "secondary", tagSets: [ { "region": "east" } ]}' --collection=events --db=reporting --out=events.json [additional options]
    

For more information on the options available, see Options.

See also

Examples

Required Access

mongoexport requires read access on the target database.

Ensure that the connecting user possesses, at a minimum, the read role on the target database.

When connecting to a mongod or mongos that enforces Authentication, ensure you use the required security parameters based on the configured authentication mechanism.

Behavior

Type Fidelity

Warning

Avoid using mongoimport and mongoexport for full instance production backups. They do not reliably preserve all rich BSON data types, because JSON can only represent a subset of the types supported by BSON. Use mongodump and mongorestore as described in MongoDB Backup Methods for this kind of functionality.

mongoexport:

For example, the following insert operation in the mongo shell uses the various shell helpers for the BSON types Date and 64-bit integer:

use test
db.traffic.insert( { _id: 1, volume: NumberLong('2980000'), date: new Date() } )

The argument to 64-bit integer must be quoted to avoid potential loss of accuracy.

Use mongoexport to export the data:

mongoexport --db=test --collection=traffic --out=traffic.json

The exported data is in Extended JSON v2.0 (Relaxed mode):

{"_id":1.0,"volume":2980000,"date":{"$date":"2019-08-05T16:18:29.559Z"}}

To output in Extended JSON v2.0 (Canonical mode), include the --jsonFormat=canonical:

mongoexport --db=test --collection=traffic --jsonFormat=canonical --out=traffic.json

The exported data is in Extended JSON v2.0 (Canonical mode):

{"_id":{"$numberDouble":"1.0"},"volume":{"$numberLong":"2980000"},"date":{"$date":{"$numberLong":"1565363188675"}}}

FIPS

mongoexport automatically creates FIPS-compliant connections to a mongod/mongos that is configured to use FIPS mode.

Read Preference

By default, mongoexport uses read preference primary. To override the default, you can specify the read preference in the --readPreference command line option or in the --uri connection string.

If you specify read preference in the URI string and the --readPreference, the --readPreference value overrides the read preference specified in the URI string.

Options

mongoexport
--help

Returns information on the options and use of mongoexport.

--verbose, -v

Increases the amount of internal reporting returned on standard output or in log files. Increase the verbosity with the -v form by including the option multiple times, (e.g. -vvvvv.)

--quiet

Runs mongoexport in a quiet mode that attempts to limit the amount of output.

This option suppresses:

  • output from database commands
  • replication activity
  • connection accepted events
  • connection closed events
--version

Returns the mongoexport release number.

--uri=<connectionString>

Specifies the resolvable URI connection string of the MongoDB deployment, enclosed in quotes:

--uri="mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]"

Starting with version 100.0 of mongoexport, the connection string may alternatively be provided as a positional parameter, without using the --uri option:

mongoexport mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/[database][?options]]

As a positional parameter, the connection string may be specified at any point on the command line, as long as it begins with either mongodb:// or mongodb+srv://. For example:

mongoexport --username joe --password secret1 mongodb://mongodb0.example.com:27017 --ssl

Only one connection string can be provided. Attempting to include more than one, whether using the --uri option or as a positional argument, will result in an error.

For information on the components of the connection string, see the Connection String URI Format documentation.

Note

Some components in the connection string may alternatively be specified using their own explicit command-line options, such as --username and --password. Providing a connection string while also using an explicit option and specifying conflicting information will result in an error.

--host=<hostname><:port>, -h=<hostname><:port>

Default: localhost:27017

Specifies the resolvable hostname of the MongoDB deployment. By default, mongoexport attempts to connect to a MongoDB instance running on the localhost on port number 27017.

To connect to a replica set, specify the replSetName and a seed list of set members, as in the following:

--host=<replSetName>/<hostname1><:port>,<hostname2><:port>,<...>

When specifying the replica set list format, mongoexport always connects to the primary.

You can also connect to any single member of the replica set by specifying the host and port of only that member:

--host=<hostname1><:port>

If you use IPv6 and use the <address>:<port> format, you must enclose the portion of an address and port combination in brackets (e.g. [<address>]).

Alternatively, you can also specify the hostname directly in the URI connection string. Providing a connection string while also using --host and specifying conflicting information will result in an error.

--port=<port>

Default: 27017

Specifies the TCP port on which the MongoDB instance listens for client connections.

Alternatively, you can also specify the port directly in the URI connection string. Providing a connection string while also using --port and specifying conflicting information will result in an error.

--ssl

Enables connection to a mongod or mongos that has TLS/SSL support enabled.

Alternatively, you can also configure TLS/SSL support directly in the URI connection string. Providing a connection string while also using --ssl and specifying conflicting information will result in an error.

For more information about TLS/SSL and MongoDB, see Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients.

--sslCAFile=<filename>

Specifies the .pem file that contains the root certificate chain from the Certificate Authority. Specify the file name of the .pem file using relative or absolute paths.

Alternatively, you can also specify the .pem file directly in the URI connection string. Providing a connection string while also using --sslCAFile and specifying conflicting information will result in an error.

For more information about TLS/SSL and MongoDB, see Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients.

--sslPEMKeyFile=<filename>

Specifies the .pem file that contains both the TLS/SSL certificate and key. Specify the file name of the .pem file using relative or absolute paths.

This option is required when using the --ssl option to connect to a mongod or mongos that has CAFile enabled without allowConnectionsWithoutCertificates.

Alternatively, you can also specify the .pem file directly in the URI connection string. Providing a connection string while also using --sslPEMKeyFile and specifying conflicting information will result in an error.

For more information about TLS/SSL and MongoDB, see Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients.

--sslPEMKeyPassword=<value>

Specifies the password to de-crypt the certificate-key file (i.e. --sslPEMKeyFile). Use the --sslPEMKeyPassword option only if the certificate-key file is encrypted. In all cases, the mongoexport will redact the password from all logging and reporting output.

If the private key in the PEM file is encrypted and you do not specify the --sslPEMKeyPassword option, the mongoexport will prompt for a passphrase. See TLS/SSL Certificate Passphrase.

Alternatively, you can also specify the password directly in the URI connection string. Providing a connection string while also using --sslPEMKeyPassword and specifying conflicting information will result in an error.

For more information about TLS/SSL and MongoDB, see Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients.

--sslCRLFile=<filename>

Specifies the .pem file that contains the Certificate Revocation List. Specify the file name of the .pem file using relative or absolute paths.

For more information about TLS/SSL and MongoDB, see Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients.

--sslAllowInvalidCertificates

Bypasses the validation checks for server certificates and allows the use of invalid certificates. When using the allowInvalidCertificates setting, MongoDB logs as a warning the use of the invalid certificate.

Warning

Although available, avoid using the --sslAllowInvalidCertificates option if possible. If the use of --sslAllowInvalidCertificates is necessary, only use the option on systems where intrusion is not possible.

Connecting to a mongod or mongos instance without validating server certificates is a potential security risk. If you only need to disable the validation of the hostname in the TLS/SSL certificates, see --sslAllowInvalidHostnames.

Alternatively, you can also disable certificate validation directly in the URI connection string. Providing a connection string while also using --sslAllowInvalidCertificates and specifying conflicting information will result in an error.

For more information about TLS/SSL and MongoDB, see Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients.

--sslAllowInvalidHostnames

Disables the validation of the hostnames in TLS/SSL certificates. Allows mongoexport to connect to MongoDB instances even if the hostname in their certificates do not match the specified hostname.

Alternatively, you can also disable hostname validation directly in the URI connection string. Providing a connection string while also using --sslAllowInvalidHostnames and specifying conflicting information will result in an error.

For more information about TLS/SSL and MongoDB, see Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients.

--username=<username>, -u=<username>

Specifies a username with which to authenticate to a MongoDB database that uses authentication. Use in conjunction with the --password and --authenticationDatabase options.

Alternatively, you can also specify the username directly in the URI connection string. Providing a connection string while also using --username and specifying conflicting information will result in an error.

If connecting to a MongoDB Atlas cluster using the MONGODB-AWS authentication mechanism, you can specify your AWS access key ID in:

See Connect to a MongoDB Atlas Cluster using AWS IAM Credentials for an example of each.

--password=<password>, -p=<password>

Specifies a password with which to authenticate to a MongoDB database that uses authentication. Use in conjunction with the --username and --authenticationDatabase options.

To prompt the user for the password, pass the --username option without --password or specify an empty string as the --password value, as in --password "" .

Alternatively, you can also specify the password directly in the URI connection string. Providing a connection string while also using --password and specifying conflicting information will result in an error.

If connecting to a MongoDB Atlas cluster using the MONGODB-AWS authentication mechanism, you can specify your AWS secret access key in:

  • this field,
  • the connection string, or
  • the AWS_SECRET_ACCESS_KEY environment variable.

See Connect to a MongoDB Atlas Cluster using AWS IAM Credentials for an example of each.

--awsSessionToken=<AWS Session Token>

If connecting to a MongoDB Atlas cluster using the MONGODB-AWS authentication mechanism, and using session tokens in addition to your AWS access key ID and secret access key, you can specify your AWS session token in:

See Connect to a MongoDB Atlas Cluster using AWS IAM Credentials for an example of each.

Only valid when using the MONGODB-AWS authentication mechanism.

--authenticationDatabase=<dbname>

Specifies the authentication database where the specified --username has been created. See Authentication Database.

If you do not specify an authentication database, mongoexport assumes that the database specified to export holds the user’s credentials.

If using the GSSAPI (Kerberos), PLAIN (LDAP SASL), or MONGODB-AWS authentication mechanisms, you must set --authenticationDatabase to $external.

Alternatively, you can also specify the authentication database directly in the URI connection string. Providing a connection string while also using --authenticationDatabase and specifying conflicting information will result in an error.

--authenticationMechanism=<name>

Default: SCRAM-SHA-1

Specifies the authentication mechanism the mongoexport instance uses to authenticate to the mongod or mongos.

Changed in version 100.1.0: Starting in version 100.1.0, mongoexport adds support for the MONGODB-AWS authentication mechanism when connecting to a MongoDB Atlas cluster.

Value Description
SCRAM-SHA-1 RFC 5802 standard Salted Challenge Response Authentication Mechanism using the SHA-1 hash function.
SCRAM-SHA-256

RFC 7677 standard Salted Challenge Response Authentication Mechanism using the SHA-256 hash function.

Requires featureCompatibilityVersion set to 4.0.

MONGODB-X509 MongoDB TLS/SSL certificate authentication.
MONGODB-AWS

External authentication using AWS IAM credentials for use in connecting to a MongoDB Atlas cluster. See Connect to a MongoDB Atlas Cluster using AWS IAM Credentials.

New in version 100.1.0.

GSSAPI (Kerberos) External authentication using Kerberos. This mechanism is available only in MongoDB Enterprise.
PLAIN (LDAP SASL) External authentication using LDAP. You can also use PLAIN for authenticating in-database users. PLAIN transmits passwords in plain text. This mechanism is available only in MongoDB Enterprise.

Alternatively, you can also specify the authentication mechanism directly in the URI connection string. Providing a connection string while also using --authenticationMechanism and specifying conflicting information will result in an error.

--gssapiServiceName=<serviceName>

Specify the name of the service using GSSAPI/Kerberos. Only required if the service does not use the default name of mongodb.

This option is available only in MongoDB Enterprise.

--gssapiHostName=<hostname>

Specify the hostname of a service using GSSAPI/Kerberos. Only required if the hostname of a machine does not match the hostname resolved by DNS.

This option is available only in MongoDB Enterprise.

--db=<database>, -d=<database>

Specifies the name of the database on which to run the mongoexport.

Alternatively, you can also specify the database directly in the URI connection string. Providing a connection string while also using --db and specifying conflicting information will result in an error.

--collection=<collection>, -c=<collection>

Specifies the collection to export.

--fields=<field1[,field2]>, -f=<field1[,field2]>

Specifies a field or fields to include in the export. Use a comma separated list of fields to specify multiple fields.

If any of your field names include white space, use quotation marks to enclose the field list. For example, if you wished to export two fields, phone and user number, you would specify --fields "phone,user number".

For csv output formats, mongoexport includes only the specified field(s), and the specified field(s) can be a field within a sub-document.

For JSON output formats, mongoexport includes only the specified field(s) and the _id field, and if the specified field(s) is a field within a sub-document, the mongoexport includes the sub-document with all its fields, not just the specified field within the document.

See: Export Data in CSV Format using --fields option for sample usage.

--fieldFile=<filename>

An alternative to --fields. The --fieldFile option allows you to specify in a file the field or fields to include in the export and is only valid with the --type option with value csv. The file must have only one field per line, and the line(s) must end with the LF character (0x0A).

mongoexport includes only the specified field(s). The specified field(s) can be a field within a sub-document.

See Use a File to Specify the Fields to Export in CSV Format for sample usage.

--query=<JSON>, -q=<JSON>

Provides a query as a JSON document (enclosed in quotes) to return matching documents in the export.

You must enclose the query document in single quotes ('{ ... }') to ensure that it does not interact with your shell environment.

The query must be in Extended JSON v2 format (either relaxed or canonical/strict mode), including enclosing the field names and operators in quotes:

For example, given a collection named records in the database test with the following documents:

{ "_id" : ObjectId("51f0188846a64a1ed98fde7c"), "a" : 1, "date" : ISODate("1960-05-01T00:00:00Z") }
{ "_id" : ObjectId("520e61b0c6646578e3661b59"), "a" : 1, "b" : 2, "date" : ISODate("1970-05-01T00:00:00Z") }
{ "_id" : ObjectId("520e642bb7fa4ea22d6b1871"), "a" : 2, "b" : 3, "c" : 5, "date" : ISODate("2010-05-01T00:00:00Z") }
{ "_id" : ObjectId("520e6431b7fa4ea22d6b1872"), "a" : 3, "b" : 3, "c" : 6, "date" : ISODate("2015-05-02T00:00:00Z") }
{ "_id" : ObjectId("520e6445b7fa4ea22d6b1873"), "a" : 5, "b" : 6, "c" : 8, "date" : ISODate("2018-03-01T00:00:00Z") }
{ "_id" : ObjectId("5cd0de910dbce4346295ae28"), "a" : 15, "b" : 5, "date" : ISODate("2015-03-01T00:00:00Z") }

The following mongoexport uses the -q option to export only the documents with the field a greater than or equal to ($gte) to 3 and the field date less than ISODate("2016-01-01T00:00:00Z") (using the extended JSON v2 format (relaxed mode) for dates { “$date”: “YYYY-MM-DDTHH:mm:ss.mmm<offset>”}):

mongoexport -d=test -c=records -q='{ "a": { "$gte": 3 }, "date": { "$lt": { "$date": "2016-01-01T00:00:00.000Z" } } }' --out=exportdir/myRecords.json

The resulting file contains the following documents:

{"_id":{"$oid":"520e6431b7fa4ea22d6b1872"},"a":3.0,"b":3.0,"c":6.0,"date":{"$date":"2015-05-02T00:00:00Z"}}
{"_id":{"$oid":"5cd0de910dbce4346295ae28"},"a":15.0,"b":5.0,"date":{"$date":"2015-03-01T00:00:00Z"}}

You can sort the results with the --sort option to mongoexport.

--type=<string>

Default: json

Specifies the file type to export. Specify csv for CSV format or json for JSON format.

If you specify csv, then you must also use either the --fields or the --fieldFile option to declare the fields to export from the collection.

--out=<file>, -o=<file>

Specifies a file to write the export to. If you do not specify a file name, the mongoexport writes data to standard output (e.g. stdout).

--jsonFormat=<canonical|relaxed>

Default: relaxed

Modifies the output to use either canonical or relaxed mode of the MongoDB Extended JSON (v2) format.

For differences between canonical and relaxed modes, see MongoDB Extended JSON (v2).

--jsonArray

Modifies the output of mongoexport to write the entire contents of the export as a single JSON array. By default mongoexport writes data using one JSON document for every MongoDB document.

--pretty

Outputs documents in a pretty-printed format JSON.

--noHeaderLine

By default, mongoexport includes the exported field names as the first line in a CSV output. --noHeaderLine directs mongoexport to export the data without the list of field names. --noHeaderLine is only valid with the --type option with value csv.

See Exclude Field Names from CSV Output for sample usage.

--slaveOk, -k

Sets the Read Preference to nearest, allowing mongoexport to read data from secondary replica set members.

--readPreference replaces --slaveOk in MongoDB 3.2. You cannot specify --slaveOk when --readPreference is specified.

Warning

Using a read preference other than primary with a connection to a mongos may produce inconsistencies, duplicates, or result in missed documents.

--readPreference=<string|document>

Default: primary

Specifies the read preference for mongoexport. The --readPreference option can take:

  • A string if specifying only the read preference mode:

    --readPreference=secondary
    
  • A quote-enclosed document to specify the mode, the optional read preference tag sets, and the optional maxStalenessSeconds:

    --readPreference='{mode: "secondary", tagSets: [ { "region": "east" } ], maxStalenessSeconds: 120}'
    

    If specifying the maxStalenessSeconds, the value must be greater than or equal to 90.

mongoexport defaults to primary read preference.

If the read preference is also included in the --uri connection string, the command-line --readPreference overrides the read preference specified in the URI string.

Warning

Using a read preference other than primary with a connection to a mongos may produce inconsistencies, duplicates, or result in missed documents.

--forceTableScan

Forces mongoexport to scan the data store directly instead of traversing the _id field index. Use --forceTableScan to skip the index. Typically there are two cases where this behavior is preferable to the default:

  1. If you have key sizes over 800 bytes that would not be present in the _id index.
  2. Your database uses a custom _id field.

When you run with --forceTableScan, mongoexport may return a document more than once if a write operation interleaves with the operation to cause the document to move.

Warning

Use --forceTableScan with extreme caution and consideration.

--skip=<number>

Use --skip to control where mongoexport begins exporting documents. See skip() for information about the underlying operation.

--limit=<number>

Specifies a maximum number of documents to include in the export. See limit() for information about the underlying operation.

--sort=<JSON>

Specifies an ordering for exported results. If an index does not exist that can support the sort operation, the results must be less than 32 megabytes.

Use --sort conjunction with --skip and --limit to limit number of exported documents.

mongoexport -d=test -c=records --sort='{a: 1}' --limit=100 --out=export.0.json
mongoexport -d=test -c=records --sort='{a: 1}' --limit=100 --skip=100 --out=export.1.json
mongoexport -d=test -c=records --sort='{a: 1}' --limit=100 --skip=200 --out=export.2.json

See sort() for information about the underlying operation.

Examples

Run mongoexport from the system command line, not the mongo shell.

Export in CSV Format

Export Data in CSV Format using --fields option

In the following example, mongoexport exports data from the collection contacts collection in the users database in CSV format to the file /opt/backups/contacts.csv.

The mongod instance that mongoexport connects to is running on the localhost port number 27017.

When you export in CSV format, you must specify the fields in the documents to export. The operation specifies the name and address fields to export.

mongoexport --db=users --collection=contacts --type=csv --fields=name,address --out=/opt/backups/contacts.csv

The output would then resemble:

name, address
Sophie Monroe, 123 Example Road
Charles Yu, 345 Sample Street

Use a File to Specify the Fields to Export in CSV Format

For CSV exports only, you can also specify the fields in a file containing the line-separated list of fields to export. The file must have only one field per line.

For example, you can specify the name and address fields in a file fields.txt:

name
address

Then, using the --fieldFile option, specify the fields to export with the file:

mongoexport --db=users --collection=contacts --type=csv --fieldFile=fields.txt --out=/opt/backups/contacts.csv

Exclude Field Names from CSV Output

The --noHeaderLine option can be used to exclude field names in a CSV export. The following example exports the name and address fields in the contacts collection in the users database and uses --noHeaderLine to suppress the output of the field names as the first line:

mongoexport --db=users --collection=contacts --type=csv --fields=name,address --noHeaderLine --out=/opt/backups/contacts.csv

The CSV output would then resemble:

Sophie Monroe, 123 Example Road
Charles Yu, 345 Sample Street

Export in JSON Format

This example creates an export of the contacts collection from the MongoDB instance running on the localhost port number 27017. This writes the export to the contacts.json file in JSON format.

mongoexport --db=sales --collection=contacts --out=contacts.json

Export from Remote Host Running with Authentication

The following example exports the contacts collection in the marketing database from a remote MongoDB instance that requires authentication.

Specify the:

Tip

Omit the --password option to have mongoexport prompt for the password:

mongoexport --host=mongodb1.example.net --port=27017 --username=someUser --authenticationDatabase=admin --collection=contacts --db=marketing --out=mdb1-examplenet.json

Alternatively, you use the --uri option to specify the host, port, username, authentication database, and db.

Tip

Omit the password in the URI string to have mongoexport prompt for the password:

mongoexport --uri='mongodb://someUser@mongodb0.example.com:27017/marketing?authsource=admin' --collection=contacts --out=mdb1-examplenet.json

Export Query Results

You can export only the results of a query by supplying a query filter with the --query option, and limit the results to a single database using the “--db” option.

For instance, this command returns all documents in the sales database’s contacts collection that contain a field named dept equal to "ABC" and the field date greater than or equal to ISODate(“2018-01-01”) (using the canonical format for dates { “$date”: “YYYY-MM-DDTHH:mm:ss.mmm<offset>”} )

mongoexport --db=sales --collection=contacts --query='{"dept": "ABC", date: { $gte: { "$date": "2018-01-01T00:00:00.000Z" } }}'

You must enclose the query document in single quotes ('{ ... }') to ensure that it does not interact with your shell environment.

Connect to a MongoDB Atlas Cluster using AWS IAM Credentials

New in version 100.1.0.

To connect to a MongoDB Atlas cluster which has been configured to support authentication via AWS IAM credentials, provide a connection string to mongoexport similar to the following:

mongoexport 'mongodb+srv://<aws access key id>:<aws secret access key>@cluster0.example.com/testdb?authSource=$external&authMechanism=MONGODB-AWS' <other options>

Connecting to Atlas using AWS IAM credentials in this manner uses the MONGODB-AWS authentication mechanism and the $external authSource, as shown in this example.

If using an AWS session token, as well, provide it with the AWS_SESSION_TOKEN authMechanismProperties value, as follows:

mongoexport 'mongodb+srv://<aws access key id>:<aws secret access key>@cluster0.example.com/testdb?authSource=$external&authMechanism=MONGODB-AWS&authMechanismProperties=AWS_SESSION_TOKEN:<aws session token>' <other options>

Note

If the AWS access key ID, secret access key, or session token include the following characters:

: / ? # [ ] @

those characters must be converted using percent encoding.

Alternatively, the AWS access key ID, secret access key, and optionally session token can each be provided outside of the connection string using the --username, --password, and --awsSessionToken options instead, like so:

mongoexport 'mongodb+srv://cluster0.example.com/testdb?authSource=$external&authMechanism=MONGODB-AWS' --username <aws access key id> --password <aws secret access key> --awsSessionToken <aws session token> <other options>

When provided as command line parameters, these three options do not require percent encoding.

You may also set these credentials on your platform using standard AWS IAM environment variables. mongoexport checks for the following environment variables when you use the MONGODB-AWS authentication mechanism:

  • AWS_ACCESS_KEY_ID
  • AWS_SECRET_ACCESS_KEY
  • AWS_SESSION_TOKEN

If set, these credentials do not need to be specified in the connection string or via their explicit options.

Note

If you chose to use the AWS environment variables to specify these values, you cannot mix and match with the corresponding explicit or connection string options for these credentials. Either use the environment variables for access key ID and secret access key (and session token if used), or specify each of these using the explicit or connection string options instead.

The following example sets these environment variables in the bash shell:

export AWS_ACCESS_KEY_ID='<aws access key id>'
export AWS_SECRET_ACCESS_KEY='<aws secret access key>'
export AWS_SESSION_TOKEN='<aws session token>'

Syntax for setting environment variables in other shells will be different. Consult the documentation for your platform for more information.

You can verify that these environment variables have been set with the following command:

env | grep AWS

Once set, the following example connects to a MongoDB Atlas cluster using these environment variables:

mongoexport 'mongodb+srv://cluster0.example.com/testdb?authSource=$external&authMechanism=MONGODB-AWS'  <other options>
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