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Databases

Tags: Computers

Class

MariaDB

Calcite

Query optimizers

Query Pushdown

Spanner

DynamoDB

  • Similar to Cassandra, has partition key and sort key
  • Can horizontally partition across different nodes, similar to cassandra
  • Similarly, need to split a partition when it gets hot
  • There’s an automated systems that defines a read capacity unit and a write capacity unit. If it exceeds, it splits
  • Note that since almost always you have hot partitions
  • Each node has multiple partitions
    • Each partition has two buckets, an allocation bucket or a burst bucket
    • To handle a read, pick from any bucket
    • To handle a write, the node needs to check the token availability of buckets in the nodes of the entire replication group
  • There’s a global admission control system, where each request router calls to a global token bucket