Design Patterns · Junior · Question 72 of 75

What does "single source of truth" mean for app data?

✓Correct answer: Each piece of data is stored in one place; everything else derives from it
2All data lives in one global variable
3Only the backend may store data

Explanation

Copies drift apart. Compute derived values instead of storing them separately.

Further reading

Wikipedia: Single source of truth ↗

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