Is there a way to query multiple hash keys in DynamoDB?

Question

Is there a way to query multiple hash keys using a single query in Amazon's AWS SDK for Java?

Here's my issue; I have a DB table for project statuses. The Hash Key is the status of a project (ie: new, assigned, processing, or complete). The range key is a set of project IDs. Currently, I've got a query setup to simply find all the projects listed as a status(hash) of "assigned" and another query set to look for a status of "processing". Is there a way to do this using a single query rather than sending multiple queries for each status I need to find? Code below:

    DynamoDBMapper mapper = new DynamoDBMapper(new AmazonDynamoDBClient(credentials));
    PStatus assignedStatus = new PStatus();
    assignedStatus.setStatus("assigned");
    PStatus processStatus = new PStatus();
    processStatus.setStatus("processing");

    DynamoDBQueryExpression<PStatus> queryAssigned = new DynamoDBQueryExpression<PStatus>().withHashKeyValues(assignedStatus);
    DynamoDBQueryExpression<PStatus> queryProcessing = new DynamoDBQueryExpression<PStatus>().withHashKeyValues(processStatus);

    List<PStatus> assigned = mapper.query(PStatus.class, queryAssigned);
    List<PStatus> process = mapper.query(PStatus.class, queryProcessing);

So basically, I'd like to know if it's possible to eliminate the queryAssigned and assigned variables and handle both assignedStatus and processStatus via the same query, process, to find projects that are not new or complete.

Answer 1

No, as of today there is no way to send multiple queries in the same request. If you're concerned about latency, you could make multiple requests simultaneously in different threads. This would require the same amount of network bandwidth as a "dual query" would if Dynamo offered it (assuming you're making 2, not hundreds).