Is it possible to ORDER results with query or scan in DynamoDB?

Question

Is it possible to ORDER results with Query or Scan API in DynamoDB?

I need to know if DynamoDB has something like [ORDER BY \'field\'] from SQL queries?

Tha

Answer 1

Use ScanIndexForward(true for ascending and false for descending) and can also limit the result using setLimit value of Query Expression.

Please find below the code where used QueryPage for finding the single record.

public void fetchLatestEvents() {
    EventLogEntitySave entity = new EventLogEntitySave();
    entity.setId("1C6RR7JM0JS100037_contentManagementActionComplete");

    DynamoDBQueryExpression queryExpression = new DynamoDBQueryExpression().withHashKeyValues(entity);
    queryExpression.setScanIndexForward(false);
    queryExpression.withLimit(1);
    queryExpression.setLimit(1);

    List result = dynamoDBMapper.queryPage(EventLogEntitySave.class, queryExpression).getResults();
    System.out.println("size of records = "+result.size() );
}

@DynamoDBTable(tableName = "PROD_EA_Test")
public class EventLogEntitySave {

        @DynamoDBHashKey
        private String id;
        private String reconciliationProcessId;
        private String vin;
        private String source;
}

public class DynamoDBConfig {
    @Bean
    public AmazonDynamoDB amazonDynamoDB() {

            String accesskey = "";
            String secretkey = "";
            //
            // creating dynamo client
            BasicAWSCredentials credentials = new BasicAWSCredentials(accesskey, secretkey);
            AmazonDynamoDB dynamo = new AmazonDynamoDBClient(credentials);
            dynamo.setRegion(Region.getRegion(Regions.US_WEST_2));
            return dynamo;
        }

    @Bean
    public DynamoDBMapper dynamoDBMapper() {
        return new DynamoDBMapper(amazonDynamoDB());
    }
}