如何使用nodejs在dynamodb中使键唯一？

Question

I have to make a key unique in dynamo db. i want to make my email unique, if the email is already existed in database then when i enter next time the same email id then it should not enter to database. it should give a response "email already exists". How can i get that?

This is the response which i am getting an employee..in this example i dont need to insert another email value like hari@gmail.com

{
            "defaultEmp": 0,
            "empName": "Hari",
            "statuses": 1,
            "designation": "store keeper",
            "id": 1,
            "storeId": 1,
            "email": "hari@gmail.com"
        }

Answer 1

您无需为电子邮件创建ID即可使其唯一。.只需在用户创建帐户时检查db中是否存在该电子邮件即可。.就这样..无需进行其他字段检查。

Answer 2

Choose accordingly, what you want to achieve partition key vs composite key .

1: you can use the designation as a partition key and email as a sort key Using sort key .

• If you want to get all of the email related to single designation this scenario is great.
• But make sure your design wont end up hitting the only designation otherwise it will end up throttling issue Provision throughput must be divide evenly .

2: you can use the email as a Partition key and designation as a Sort key or only email as Partition key.

• For a single email what are the designation available

3: simply select email as Partition key.

NOTE:

-make sure email and designation composite Primary key are unique else it will overwrite data.

-This is my first contribution :) Correct me if I am wrong and feel free to give any suggestion. Thanks!