Dynamo db sorting

Question

I have a scenario in which I will have to list the incoming requests of a user sorted based on creation time and priority(High, Medium, Low) along with pagination. Is there a way to achieve this in dynamoDb ?

Right now I'm using a secondary Index like userId-createdAt-index which sorts data based on creation time and further sorting the request based on priority separately in the frontend. Somebody please provide a right solution for this.

Answer 1

You're correct to use an index with a sort key. This could also be your primary index, thus reducing how many indexes you need, but that of course depends on whether you already have a sort key on your primary.

DDB guarantees the order of a sorted index, so paging will correctly page by date for you, if you want to reverse the order, add the ScanIndexForward to your query and set it to false .

Your model of query / sort by date at the DB level, then sort by other fields at the application level is normal and correct.

Depending very much on your use-case, another option to consider is querying by priority by using KeyConditions and adding the condition #priority EQ :priority , but I doubt this is what you want.