mongoexport fields from subdocuments to csv

Question

I am trying to export a field from a subdocument with no luck.
Here is my syntax;

mongoexport -d test -c accounts -f account_number,situses.coordinates -         


        

Answer 1

It looks like this is a known bug to be fixed in 3.0.5.
See this; https://jira.mongodb.org/browse/TOOLS-657

Answer 2

There is mistake in your syntax.

From mongo version 3.0.0, mongoexport removed the --type = csv option. Use the --type=csv option to specify CSV format for the output.

You should use :

mongoexport --db tests --collection accounts --type=csv --fields account_number,situses --out coordinates.csv

For nested fields you should use :

mongoexport --db tests --collection accounts --csv --fields 'account_number,situses.0.coordinates'  --out /home/vishwas/c1.csv 

EDIT for mongo 3.0 with sub documents:

You need to create separate collection with required fields from subdocuments like -

db.test.aggregate({"$unwind":"$situses"},{"$project":{"_id":0,"account_number":1,"siteUsesCo":"$situses.coordinates"}},{"$out" : "forcsv"}) 

If you want only one field from subdocument then use aggregation like -

db.test.aggregate({"$unwind":"$situses"},{"$limit":1},{"$project":{"_id":0,"account_number":1,"siteUsesCo":"$situses.coordinates"}},{"$out" : "forcsv"})

And then export from forcsv collection like-

mongoexport --db test --collection forcsv --csv --fields 'account_number,siteUsesCo'  --out coordinates.csv

And after exporting delete collection forcsv.

Answer 3

And one more solution, where you can configure output in flexible way

mongo host:port/test --quiet query.js -u username -p passw0rd > accounts.csv

and query.js:

db = db.getSiblingDB('test');

db.getCollection('accounts').find({}, {account_number:1, situses:1, _id:0}).forEach(
    function(item_data) { print(`${item_data.account_number},${item_data.situses[0].coordinates}`); });