Database Scaling
Index it, replicate it, then shard it, in that order and only as far as the numbers force you.
5 lessons · ~52 min · free
By the end you can
- Reach for indexes before architecture, and know their write cost
- Scale reads with replicas and reason about replication lag out loud
- Shard by the right key and spot hot-key skew before it happens
- Choose SQL or NoSQL from access patterns instead of fashion
- Present the escalation ladder (index, cache, replicate, shard) in an interview
Lessons
Start the course- The database is always the bottleneck10 minRead-heavy vs write-heavy, and why an index is the first move, not a bigger machine.
- Read replicas and the lag they bring11 minLeader-follower replication, scaling reads, and the stale read that bites you in the demo.
- Splitting the data itself12 minHash vs range partitioning, hot keys, and why resharding is the move you plan for early.
- SQL vs NoSQL, minus the tribalism10 minWhat actually differs: schemas, joins, transactions, and scale-out defaults, by access pattern.
- The escalation ladder9 minIndex, cache, replicate, shard: the order, the signals for each step, and the traps.
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Design with it after
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