I am modeling a simple application an I would like to use DynamoDB as my storage. I need to store a all order from a ecommerce website. It is possible to query using the order_id and the user email.
Looking at the dynamodb documentation, I think the best approach is to user the order_id (Most of my queries will be made on this index) as my primary key (Partition key).
And what about email? I would like a secondary index, but I am bit lost. What is the best approach?
It looks like a Global Secondary Index on the email attribute would solve the problem:
when you need to lookup by order_id, you use the GetItem operation and specify that order_id as the primary key
when you need to lookup by email, you use the Query API on the GSI and specify the email as the partition key.
GSI have independent read capacity units - since you said you will use order_id most of the time, you could provision more RCU to the main table than the GSI.
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