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mongoexport
mongoexport
¶
Synopsis¶
mongoexport
is a utility that produces a JSON or CSV export
of data stored in a MongoDB instance. See the
Import and Export MongoDB Data document for a more in depth
usage overview, and the mongoimport document for more
information regarding the mongoimport
utility, which
provides the inverse “importing” capability.
Note
Do not use mongoimport
and mongoexport
for
full-scale backups because they may not reliably capture data type
information. Use mongodump
and mongorestore
as
described in MongoDB Backup Methods for this kind of
functionality.
Options¶
-
mongoexport
¶
-
--help
¶
Returns a basic help and usage text.
-
--verbose
,
-v
¶
Increases the amount of internal reporting returned on the command line. Increase the verbosity with the
-v
form by including the option multiple times, (e.g.-vvvvv
.)
-
--version
¶
Returns the version of the
mongoexport
utility.
-
--host
<hostname><:port>
¶ Specifies a resolvable hostname for the
mongod
from which you want to export data. By defaultmongoexport
attempts to connect to a MongoDB process running on the localhost port number27017
.Optionally, specify a port number to connect a MongoDB instance running on a port other than
27017
.To connect to a replica set, you can specify the replica set seed name, and a seed list of set members, in the following format:
-
--port
<port>
¶ Specifies the port number, if the MongoDB instance is not running on the standard port. (i.e.
27017
) You may also specify a port number using themongoexport --host
command.
-
--ipv6
¶
Enables IPv6 support that allows
mongoexport
to connect to the MongoDB instance using an IPv6 network. All MongoDB programs and processes, includingmongoexport
, disable IPv6 support by default.
-
--ssl
¶
New in version 2.4: MongoDB added support for SSL connections to
mongod
instances in mongoexport.Note
SSL support in mongoexport is not compiled into the default distribution of MongoDB. See Connect to MongoDB with SSL for more information on SSL and MongoDB.
Additionally, mongoexport does not support connections to
mongod
instances that require client certificate validation.Allows
mongoexport
to connect tomongod
instance over an SSL connection.
-
--username
<username>
,
-u
<username>
¶ Specifies a username to authenticate to the MongoDB instance, if your database requires authentication. Use in conjunction with the
mongoexport --password
option to supply a password.
-
--password
<password>
,
-p
<password>
¶ Specifies a password to authenticate to the MongoDB instance. Use in conjunction with the
--username
option to supply a username.If you specify a
--username
and do not pass an argument to--password
,mongoexport
will prompt for a password interactively. If you do not specify a password on the command line,--password
must be the last argument specified.
-
--authenticationDatabase
<dbname>
¶ New in version 2.4.
Specifies the database that holds the user’s (e.g
--username
) credentials.By default,
mongoexport
assumes that the database specified to the--db
argument holds the user’s credentials, unless you specify--authenticationDatabase
.See
userSource
, system.users Privilege Documents and User Privilege Roles in MongoDB for more information about delegated authentication in MongoDB.
-
--authenticationMechanism
<name>
¶ New in version 2.4.
Specifies the authentication mechanism. By default, the authentication mechanism is
MONGODB-CR
, which is the MongoDB challenge/response authentication mechanism. In MongoDB Enterprise,mongoexport
also includes support forGSSAPI
to handle Kerberos authentication.See Deploy MongoDB with Kerberos Authentication for more information about Kerberos authentication.
-
--dbpath
<path>
¶ Specifies the directory of the MongoDB data files. If used, the
--dbpath
option enablesmongoexport
to attach directly to local data files and insert the data without themongod
. To run with--dbpath
,mongoexport
needs to lock access to the data directory: as a result, nomongod
can access the same path while the process runs.
-
--directoryperdb
¶
Use the
--directoryperdb
in conjunction with the corresponding option tomongod
, which allowsmongoexport
to export data from MongoDB instances that have every database’s files saved in discrete directories on the disk. This option is only relevant when specifying the--dbpath
option.
-
--journal
¶
Allows
mongoexport
operations to access the durability journal to ensure that the export is in a valid state. This option is only relevant when specifying the--dbpath
option.
-
--db
<db>
,
-d
<db>
¶ Use the
--db
option to specify the name of the database that contains the collection you want to export.
-
--collection
<collection>
,
-c
<collection>
¶ Use the
--collection
option to specify the collection that you wantmongoexport
to export.
-
--fields
<field1[,field2]>
,
-f
<field1[,field2]>
¶ Specify 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, themongoexport
includes the sub-document with all its fields, not just the specified field within the document.
-
--fieldFile
<file>
¶ As 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--csv
option. 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.
Example
Given a collection named
records
in the databasetest
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 fielda
greater than or equal to ($gte
) to3
:mongoexport -d test -c records -q "{ a: { \$gte: 3 } } }" --out exportdir/myRecords.json
The resulting file contains the following documents:
{ "_id" : { "$oid" : "520e6431b7fa4ea22d6b1872" }, "a" : 3, "b" : 3, "c" : 6 } { "_id" : { "$oid" : "520e6445b7fa4ea22d6b1873" }, "a" : 5, "b" : 6, "c" : 8 }
-
--csv
¶
Changes the export format to a comma separated values (CSV) format. By default
mongoexport
writes data using one JSON document for every MongoDB document.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.
-
--jsonArray
¶
Modifies the output of
mongoexport
to write the entire contents of the export as a single JSON array. By defaultmongoexport
writes data using one JSON document for every MongoDB document.
-
--slaveOk
,
-k
¶
Allows
mongoexport
to read data from secondary or slave nodes when usingmongoexport
with a replica set. This option is only available if connected to amongod
ormongos
and is not available when used with the “mongoexport --dbpath
” option.This is the default behavior.
-
--out
<file>
,
-o
<file>
¶ Specify 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
).
-
--forceTableScan
¶
New in version 2.2.
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:- If you have key sizes over 800 bytes that would not be present
in the
_id
index. - 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.- If you have key sizes over 800 bytes that would not be present
in the
Usage¶
In the following example, mongoexport
exports the
collection contacts
from the users
database from the
mongod
instance running on the localhost port number
27017
. This command writes the export data in CSV format
into a file located at /opt/backups/contacts.csv
. The
fields.txt
file contains a line-separated list of fields to
export.
The next example creates an export of the collection contacts
from the MongoDB instance running on the localhost port number 27017
,
with journaling explicitly enabled. This writes the export to the
contacts.json
file in JSON format.
The following example exports the collection contacts
from the
sales
database located in the MongoDB data files located at
/srv/mongodb/
. This operation writes the export to standard output
in JSON format.
Warning
The above example will only succeed if there is no mongod
connected to the data files located in the /srv/mongodb/
directory.
The final example exports the collection contacts
from the
database marketing
. This data resides on the MongoDB instance
located on the host mongodb1.example.net
running on port
37017
, which requires the username user
and the password
pass
.