Difference in the index when using @CompoundIndex and creating with ensureIndex

[ryee]

Hi,
I'm using Spring Data 1.0.0.M5 with Mongo 2.0.1 and I notice that there is a difference in the index that gets created when I use @CompoundIndex and when I use DB.ensureIndex. My intent is to create a compound geoSpatialIndex using the 'loc' and 'type' fields in my document. The loc field has the lon/lat coords that I am indexing on. The type field is just a String field.
When I use the following @CompoundIndex annotation:
@CompoundIndexes(value={
@CompoundIndex(name="location_type_idx", def="{'loc' : '2d', 'type':1}")
})

the index that is created in Mongo is:
{ "v" : 1, "key" : { "loc" : "2d", "type" : NumberLong(1) }, "ns" : "myCollection.xyz", "name" : "location_type_idx", "dropDups" : false, "sparse" : false }

If I use the following code to create the index,
DB db
Mongo m;
m = new Mongo(...);
db = m.getDB(...);
db.getCollection("myCollection").ensureIndex(new BasicDBObject("loc","2d").append("type",1));

the index that is created in Mongo is:
{ "v" : 1, "key" : { "loc" : "2d", "type" : 1 }, "ns" : "myCollection.xyz", "name" : "loc_2d_type_1" }


Note that the first one has "type" : NumberLong(1) and the second has "type" : 1

The problem that I have is that the first index,
{ "v" : 1, "key" : { "loc" : "2d", "type" : NumberLong(1) }, "ns" : "myCollection.xyz", "name" : "location_type_idx", "dropDups" : false, "sparse" : false }

doesn't seem to work. I get a NullPointerException on line 495 in MongoTemplate.geoNear.

Does anyone know what I am doing wrong here?

Thanks for any help in advance.

Richard

[Oliver Gierke]

I don't think the NPE is related to the indexes getting created slightly different. Would you mind upgrading to SD MongoDB 1.0 GA. We have fixed quite a few [0], [1] issues in geoNear(…) with that release.

[0] https://jira.springsource.org/browse/DATAMONGO-336
[1] https://jira.springsource.org/browse/DATAMONGO-341