practice dynamodb & node.js
$ docker pull instructure/dynamo-local-admin
$ docker run -p 8000:8000 -it --rm instructure/dynamo-local-admin
https://hub.docker.com/r/amazon/dynamodb-local
https://github.com/instructure/dynamo-local-admin-docker
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/GSI.html#GSI.Reading
https://stackoverflow.com/questions/47675920/aws-dynamodb-data-with-and-or-without-types
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/SecondaryIndexes.html
https://stackoverflow.com/questions/58670063/how-to-delete-multiple-rows-in-dynamodb
https://github.com/aaronshaf/dynamodb-admin
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/GSI.html
https://rockset.com/blog/3-cost-cutting-tips-for-amazon-dynamodb/
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/bp-relational-modeling.html