Day 7 drills

Written on paper first. These are the URL shortener design, broken into its hardest decisions. Answer with numbers.

D1 (scale: write rate, read rate, 5-year storage in TB):

D2 (short code length: 62^6 vs 62^7, how many characters):

D3 (API: create and redirect endpoints, 301 vs 302):

D4 (short-code scheme: counter+base62 vs hash vs random, pick one):

D5 (the bottleneck, the fix, and the database read rate after a 90% cache hit rate):