Meteor: how to search for only distinct field values aka a collection.distinct("fieldname") similar to Mongo's

You can just use underscore.js, which comes with Meteor - should be fine for the suggested use case. You might run into performance problems if you try this on a vast data set or run it repeatedly, but it should be adequate for common-or-garden usage:

var distinctEntries = _.uniq(Collection.find({}, {
    sort: {myField: 1}, fields: {myField: true}
}).fetch().map(function(x) {
    return x.myField;
}), true);

That will return the distinct entries in myField for all documents in Collection. Apologies if the one-liner looks a bit unwieldy; the sort and fields options and the true flag are just to make it more efficient.

If you'd prefer to do this on the server and thus save client memory and bandwidth try this aggregator package. It wraps mongodb's "distinct" function. https://github.com/zvictor/meteor-mongo-server/

A Non-Underscore, pure mongo solution would be to access the raw collection directly. This involves a Promise (though you can use await to await the resolved value).

Note: it will run on the MongoDB server and return distinct values to the client.

Collection._collection.rawCollection().distinct('fieldname').then(distinctValues => console.log(distinctValues))