new: DynamoDB

DynamoDB.md

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+# DynamoDB
+
+It's a [[NoSQL]] [[Database]] from [[AWS]]
+
+## Differences from SQL Database
+
+- Records of a table can have different fields
+- Tables can be partitioned using **partition keys**, I think you cannot query *fast* across different partitions. I think an analogy to **partition keys** would be like having a table across multiple databases in [[SQL]] Databases
+- Tables also have **sort keys**, this determines how records are ordered, and you can only query contiguous records, I think you cannot filter nor change the order (maybe only reverse the default order)
+- So basically **partition keys** and **sort keys** determines how the table can be queried. This limitations is the tradeoff that makes [[DynamoDB]] fast.
+- There are some improvements with the connection management, I think it allows a lot more concurrent connections, but I don't know the details.
+
+## Use cases
+
+- High scalability
+- Better integration with serverless architecture, because of better connection management
+
+## What led to learning this
+
+- Podcast: Full Stack Radio: 139: Alex DeBrie - DynamoDB for Relational Database Diehards <https://fullstackradio.com/episodes/139-20f6bb42>