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Web Development26 sections · 2h ago

Caching with Redis

Keep hot data in memory with a TTL, so busy endpoints skip the database.

Key point

Redis is single-threaded: never run KEYS * in production.

cache.js

api

1const cached = await redis.get('user:42');
2if (cached) return JSON.parse(cached);
3const data = await fetchUser(42);
4await redis.set('user:42', data, 'EX', 60);
5return data;

zsh~/api

$ docker compose up -d
✔ Container redis  Started

Mathdet(A) = ad − bc

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Code
```
fn hash(k: &str) {
  siphash24(k)
}
```
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Terminal
```
$ pnpm build
✓ Built in 412ms
```
Commands and output
Tip
Index the foreign keys you query by.
Coloured callouts
Interview Q
What is the event loop?
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Checklist
- Master LRU cache
- Write unit tests
- Benchmark latency
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Table
MethodCost
LookupO(1)
Compare side by side
Math
∫ e^x dx = e^x + C
LaTeX formulas
Diagram
Client→Cache→DB
Flowcharts from text
Quote
“Premature optimization is the root of all evil.”— Donald Knuth
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