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by Ao7bei3s 897 days ago
DynamoDB can't even represent SELECT * FROM items LIMIT 25 OFFSET 100. It's just not designed for that. It's not meant to be a relational DB replacement.

How would you do it? Assume we want proper pagination, and not rewrite the app for cursor based "Load more" style pagination. Why? Because the React Admin provider API insists. https://github.com/marmelab/react-admin/issues/1510
2 comments
belter 897 days ago
Your example itself shows why you would not want to do this. The database still has to read through all the rows up to the OFFSET point...

You are not supposed to do the same query patterns. My argument is that you can substitute your relational database, by changing the app and the layout of the data to match the proper patterns for DynamoDB.

"Migrating to DynamoDB from a relational database" - https://docs.aws.amazon.com/amazondynamodb/latest/developerg...

""How to model one-to-many relationships in DynamoDB" - https://www.alexdebrie.com/posts/dynamodb-one-to-many/

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earthling8118 896 days ago
If you place arbitrary restrictions upon it then of course it won't fit your model. Dynamo can handle pagination easily by passing in the last seen ID in the request. We used IDs that were lexigraphically sortable by time which has some nice properties such as never losing your position due to extra items being inserted in the middle of your query. Offset/limit aren't fun to work with.

You can go further by using the streams feature to dump your data into an analytical database for your querying needs.

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