CURRICULUM

SQL: Four Difficulties, 4000 Levels

SQL has four difficulties with 1000 levels each and ten questions per level; explain the result before adding speed. Data SQL levels ask what a query returns; read the joins and filters before the result.

数据 SQL 基础闯关Data SQL Basics1000 关数据 SQL 进阶闯关Data SQL Intermediate1000 关数据 SQL 高阶闯关Data SQL Advanced1000 关数据 SQL 挑战闯关Data SQL Challenge1000 关

How it works

  1. Start at the basic difficulty.
  2. Ten questions per level; clear one to unlock the next.
  3. Review at 1/3/7/14/30 days.

FAQ

Which difficulty?

Start at basic and move up when accuracy stays above 80%.

How many levels each?

1000.