Counting things in groups

Intro to SQL · Chapter 2 · Sidd

Three things today. First: rows that quietly vanish when you filter.

by the end of today

Turn a long list of orders into one number per group, and know nothing went missing on the way.

  1. Rows that quietly vanishnew today
  2. Many rows into one per groupnew today
  3. Sorting and keeping the top fewnew today
  4. Your turn on the real tableyou drive