How to create a compound index in MongoDB through Java driver?

Question

I want to create compound index on Age and Name in MongoDB through Java driver and here is my syntax:

coll.ensureIndex(new BasicDBObject("Age", 1),new BasicDBObject("Name", -1));
List <DBObject> list = coll.getIndexInfo();

  for (DBObject o : list) {
       System.out.println(o);
    }

but it create only 1 index not compund index and give me result this:

{ "v" : 1 , "key" : { "_id" : 1} ,"ns" :"EmployeeData.EmpPersonalData", "name":"_id_"}
{ "v" : 1 , "key" : { "Age" : 1} , "ns" : "EmployeeData.EmpPersonalData" , "name" : "Age_1" , "Name" : -1}

So how can compund index on collection can be created through java driver?

Beryllium · Accepted Answer · 2013-08-19 20:54:14Z

27

If you look at your code, you have actually called ensureIndex with two parameters. Your first parameter was the key and your second parameter became some extra field: Name: -1.

What you are looking to pass in the first parameter is this object {"Age":1, "Name":-1}. What you actually passed was {"Age":1}, {"Name":-1}.

So you want to do something like this:

BasicDBObject obj = new BasicDBObject();
obj.put("Age", 1);
obj.put("Name", -1);
coll.ensureIndex(obj);

Note that the index will be created with a default name. To provide a specific name do the following:

coll.ensureIndex(obj, "MyName");

edited Aug 19, 2013 at 20:54

Beryllium

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answered Jul 15, 2012 at 4:16

Gates VP

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2 Comments

Gates VP Over a year ago

In Stackoverflow, I get points if you mark the answer as correct and/or vote it up. It also tells other people that this was the correct answer. Would you be able to do that?

jad001 Over a year ago

why not @Gates ! sorry i must have done before but i am new to this site :)

user4833611 · Accepted Answer · 2015-08-27 09:46:58Z

5

You can try this according to the official documentation.

import org.bson.Document;
db.getCollection("restaurants").createIndex(new Document("cuisine", 1).append("address.zipcode", -1));

Official Mongo DB Driver Java documentation

answered Aug 27, 2015 at 9:46

user4833611

Comments

Stephan Henningsen · Accepted Answer · 2025-07-04 07:55:39Z

4

A more modern and perhaps fluent approach using the factory methods could be:

import com.mongodb.client.model.Indexes;

collection
    .createIndex(
        Indexes.compoundIndex(
            Indexes.ascending("Age"),
            Indexes.descending("Name")
        )
    );

Found in the manual. Formatted for clarity; post-format to your own taste.

edited Jul 4 at 7:55

answered Jan 5, 2020 at 23:23

Stephan Henningsen

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