mongoexport - Export Data from Mongo DB

mongoexport is a utility that produces a JSON or CSV export of data stored in a MongoDB instance. 

Considerations

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 for this kind of functionality.

To preserve type information, mongoexport and mongoimport uses the strict mode representation for certain types.

For example, the following insert operation in the mongo shell uses the shell mode representation for the BSON types data_date and data_numberlong:

use test

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

The argument to data_numberlong 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 strict mode representation to preserve type information:

{ "_id" : 1, "volume" : { "$numberLong" : "2980000" }, "date" : { "$date" : "2014-03-13T13:47:42.483-0400" } }

Required Access

mongoexport requires read access on the target database.

Ensure that the connecting user posseses, 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.

Read Preference

mongoexport defaults to primary read preference when connected to a mongos or a replica set.You can override the default read preference using the --readPreference option.

IMPORTANT

Using a non-primary read preference on a mongos may produce inconsistencies in data, including duplicates or missing documents.

Options

Changed in version 3.0.0: mongoexport removed the --dbpath as well as related --directoryperdband --journal options. You must use mongoexport while connected to a mongod instance.

Changed in version 3.0.0: mongoexport removed the --csv option. Use the --type=csv option to specify CSV format for the output.

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 the 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.

D:\MongoDB\bin>mongoexport --versionmongoexport version: 3.2.1git version: 17a5573551a0c3e33603f98375f144f1dd20b745

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

Default: localhost:27017

Specifies a resolvable hostname for the mongod to which to connect. By default, the mongoexportattempts 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:

<replSetName>/<hostname1><:port>,<hostname2><:port>,<...>

You can always connect directly to a single MongoDB instance by specifying the host and port number directly.

Changed in version 3.0.0: 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>]).

--port <port>

Default: 27017

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

--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.

--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.

Changed in version 3.0.0: If you do not specify an argument for --password, mongoexport returns an error.

Changed in version 3.0.2: If you wish mongoexport 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 "" .

--authenticationDatabase <dbname>

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

--authenticationMechanism <name>

Default: SCRAM-SHA-1

Changed in version 2.6: Added support for the PLAIN and MONGODB-X509 authentication mechanisms.

Changed in version 3.0: Added support for the SCRAM-SHA-1 authentication mechanism. Changed default mechanism to SCRAM-SHA-1.

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

Value	Description
SCRAM-SHA-1	RFC 5802 standard Salted Challenge Response Authentication Mechanism using the SHA1 hash function.
MONGODB-CR	MongoDB challenge/response authentication.
MONGODB-X509	MongoDB TLS/SSL certificate authentication.
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.

--db <database>, -d <database>

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

--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.

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.

--fieldFile <filename>

An alternative to --fields. The --fieldFile option allows you to specify in a file the field or fields to includein 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.

--query <JSON>, -q <JSON>

Provides a JSON document as a query that optionally limits the documents returned in the export. Specify JSON in strict format.

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

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

{ "_id" : ObjectId("51f0188846a64a1ed98fde7c"), "a" : 1 }

{ "_id" : ObjectId("520e61b0c6646578e3661b59"), "a" : 1, "b" : 2 }

{ "_id" : ObjectId("520e642bb7fa4ea22d6b1871"), "a" : 2, "b" : 3, "c" : 5 }

{ "_id" : ObjectId("520e6431b7fa4ea22d6b1872"), "a" : 3, "b" : 3, "c" : 6 }

{ "_id" : ObjectId("520e6445b7fa4ea22d6b1873"), "a" : 5, "b" : 6, "c" : 8 }

The following mongoexport uses the -q option to export only the documents with the field a greater than or equal to ($gte) to 3:

mongoexport -d test -c records -q '{ a: { $gte: 3 } }' --out exportdir/myRecords.json

The resulting file contains the following documents:

{ "_id" : { "$oid" : "520e6431b7fa4ea22d6b1872" }, "a" : 3, "b" : 3, "c" : 6 }

{ "_id" : { "$oid" : "520e6445b7fa4ea22d6b1873" }, "a" : 5, "b" : 6, "c" : 8 }

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

--type <string>

Default: json

New in version 3.0.0.

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).

--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

New in version 3.0.0.

Outputs documents in a pretty-printed format JSON.

--slaveOk, -k

Deprecated since version 3.2.

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

--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>

Specify the read preference for mongoexport.

mongoexport defaults to primary read preference when connected to a mongos or a replica set.

Otherwise, mongoexport defaults to nearest.

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.

--limit <number>

Specifies a maximum number of documents to include in the export. 

--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

Use

Export in CSV Format

Changed in version 3.0.0: mongoexport removed the --csv option. Use the --type=csv option to specify CSV format for the output.

In the following example, mongoexport exports data from the collection contacts collection in the usersdatabase 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

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

Changed in version 3.0.0: mongoexport removed the --csv option and replaced with the --type option.

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 from the marketing database, which requires authentication.

This data resides on the MongoDB instance located on the host mongodb1.example.net running on port37017, which requires the username user and the password pass.

mongoexport --host mongodb1.example.net --port 37017 --username user --password pass --collection contacts --db marketing --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 field with a value of 1.

mongoexport --db sales --collection contacts --query '{"field": 1}'

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

Few other Options:

--ipv6

Removed in version 3.0.

Enables IPv6 support and allows mongoexport to connect to the MongoDB instance using an IPv6 network. Prior to MongoDB 3.0, you had to specify --ipv6 to use IPv6. In MongoDB 3.0 and later, IPv6 is always enabled.

--ssl

New in version 2.6.

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

Changed in version 3.0: Most MongoDB distributions now include support for TLS/SSL. See Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients for more information about TLS/SSL and MongoDB.

--sslCAFile <filename>

New in version 2.6.

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.

Changed in version 3.0: Most MongoDB distributions now include support for TLS/SSL. See Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients for more information about TLS/SSL and MongoDB.

WARNING

For SSL connections (--ssl) to mongod and mongos, if the mongoexport runs without the --sslCAFile, mongoexport will not attempt to validate the server certificates. This creates a vulnerability to expired mongod and mongos certificates as well as to foreign processes posing as valid mongod or mongos instances. Ensure that you always specify the CA file to validate the server certificates in cases where intrusion is a possibility.

--sslPEMKeyFile <filename>

New in version 2.6.

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 CAFileenabled without allowConnectionsWithoutCertificates.

Changed in version 3.0: Most MongoDB distributions now include support for TLS/SSL. See Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients for more information about TLS/SSL and MongoDB.

--sslPEMKeyPassword <value>

New in version 2.6.

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 mongoexportwill 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 SSL Certificate Passphrase.

Changed in version 3.0: Most MongoDB distributions now include support for TLS/SSL. See Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients for more information about TLS/SSL and MongoDB.

--sslCRLFile <filename>

New in version 2.6.

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

Changed in version 3.0: Most MongoDB distributions now include support for TLS/SSL. See Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients for more information about TLS/SSL and MongoDB.

--sslAllowInvalidCertificates

New in version 2.6.

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.

Changed in version 3.0: Most MongoDB distributions now include support for TLS/SSL. See Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients for more information about TLS/SSL and MongoDB.

--sslAllowInvalidHostnames

New in version 3.0.

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

Changed in version 3.0: Most MongoDB distributions now include support for TLS/SSL. See Configure mongod and mongos for TLS/SSL and TLS/SSL Configuration for Clients for more information about TLS/SSL and MongoDB.

--sslFIPSMode

New in version 2.6.

Directs the mongoexport to use the FIPS mode of the installed OpenSSL library. Your system must have a FIPS compliant OpenSSL library to use the --sslFIPSMode option.

NOTE

FIPS-compatible SSL is available only in MongoDB Enterprise. See Configure MongoDB for FIPS for more information.