amazon web services - DynamoDB create index on map or list type

Question

I'm trying to add an index to an attribute inside of a map object in DynamoDB and can't seem to find a way to do so. Is this something that is supported or are indexes really only allowed on scalar values? The documentation around this seems to be quite sparse. I'm hoping that the indexing functionality is similar to MongoDB but so far the approaches I've taken of referencing the attribute to index using dot syntax has not been successful. Any help or additional info that can be provided is appreciated.

Answer 1

Indexes can be built only on top-level JSON attributes. In addition, range keys must be scalar values in DynamoDB (one of String, Number, Binary, or Boolean).

From http://aws.amazon.com/dynamodb/faqs/:

Q: Is querying JSON data in DynamoDB any different?

No. You can create a Global Secondary Index or Local Secondary Index on any top-level JSON element. For example, suppose you stored a JSON document that contained the following information about a person: First Name, Last Name, Zip Code, and a list of all of their friends. First Name, Last Name and Zip code would be top-level JSON elements. You could create an index to let you query based on First Name, Last Name, or Zip Code. The list of friends is not a top-level element, therefore you cannot index the list of friends. For more information on Global Secondary Indexing and its query capabilities, see the Secondary Indexes section in this FAQ.

Q: What data types can be indexed?

All scalar data types (Number, String, Binary, and Boolean) can be used for the range key element of the local secondary index key. Set, list, and map types cannot be indexed.