Question

How do you create a Geospatial Haystack Index using the 10gen C# Driver for MongoDB

JS Example:

db.foo.ensureIndex({ pos : "geoHaystack", type : 1 }, { bucketSize : 1 })

C# Example that does not work:

BsonDocument keys = new BsonDocument();
keys.Add("pos", "geoHaystack");
keys.Add("type", "1");

IMongoIndexKeys indexKeys = new IndexKeysDocument(keys);

IndexOptionsDocument indexOptions = new IndexOptionsDocument("bucketSize", new BsonInt32(1));

collection.CreateIndex(indexKeys, indexOptions);

Gives this error:

MongoDB.Driver.MongoSafeModeException : Safemode detected an error ‘can only have 1 index plugin / bad index key pattern’. (Response was { “err” : “can only have 1 index plugin / bad index key pattern”, “code” : 13007, “n” : 0, “connectionId” : 6, “ok” : 1.0 }).

So if I remove the ‘type’ key, like this:

BsonDocument keys = new BsonDocument();
keys.Add("pos", "geoHaystack");

IMongoIndexKeys indexKeys = new IndexKeysDocument(keys);

IndexOptionsDocument indexOptions = new IndexOptionsDocument("bucketSize", new BsonInt32(1));

collection.CreateIndex(indexKeys, indexOptions);

I get this error:

MongoDB.Driver.MongoSafeModeException : Safemode detected an error ‘no other fields specified’. (Response was { “err” : “no other fields specified”, “code” : 13317, “n” : 0, “connectionId” : 7, “ok” : 1.0 }).

Answer 1

Actually the problem was index direction was specified as a string value

 keys.Add("type", "1");

Change it to integer

 keys.Add("type", 1);

This will work as expected