SerCeMan

# Designing Data-Intensive Applications: The Big Ideas Behind Reliable, Scalable, and Maintainable Systems

1. **Chapter 1. Reliable, Scalable and Maintainable Applications**
  1. R faults != failures, faults cause failures. Systems should be fault-tolerant, resistant to some types of faults 
  2. S Amazon cares about 99.9% percentile because people with higher latencies usually are people who have the most data and therefore, they’re most valuable customers
  3. S tail latency amplification - multiple requests one critical path during one page served
2. **Chapter 2. Data Models and Query Languages**
  1. Hierarchical model - imperative querying, no way to change schema, children are ordered, no many-to-many
  2. CODASYL (network) vs SQL
  3. NoSQL - often no schema (precisely - schema on read vs schema on write)

tadast

In the console

export SLACK_DEVELOPER_MENU=true
open /Applications/Slack.app

In slack UI

right-click on anything -> inspect element