DynamoDB's withLimit clause with DynamoDBMapper.query
amazon-dynamodb, java
Solution
In March 2013 on the AWS forums a user complained about the same problem.
A representative from Amazon sent him to use the queryPage function.
It seems as if the limit is not preserved for elements but rather a limit on chunk of elements retrieved in a single API call, and the queryPage might help.
You could also look into the pagination loading strategy configuration
Also, you can always open a Github issue for the team.
Problem
I am using DynamoDBMapper for a class, let's say "User" (username being the primary key) which has a field on it which says "Status". It is a Hash+Range key table, and everytime a user's status changes (changes are extremely infrequent), we add a new entry to the table alongwith the timestamp (which is the range key). To fetch the current status, this is what I am doing: ``` DynamoDBQueryExpression expr = new DynamoDBQueryExpression(new AttributeValue().withS(userName)) .withScanIndexForward(false).withLimit(1); PaginatedQueryList<User> result = this.getMapper().query(User.class, expr); if(result == null || result.size() == 0) { return null; } for(final User user : result) { System.out.println(user.getStatus()); } ``` This for some reason, is printing all the statuses a user has had till now. I have set `scanIndexForward` to false so that it is in descending order and I put limit of `1`. I am expecting this to return the latest single entry in the table for that username. However, when I even look into the wire logs of the same, I see a huge amount of entries being returned, much more than 1. For now, I am using: ``` final String currentStatus = result.get(0).getStatus(); ``` What I am trying to understand here is, what is whole point of the `withLimit` clause in this case, or am I doing something wrong?