Code Arena

Skill path

1. 1
   Rookie Rookie

   SELECT, WHERE, ORDER BY
   +0 XP
2. 2
   Apprentice Apprentice

   JOINs, GROUP BY, aggregates
   +500 XP
3. 3
   Engineer Engineer

   Window functions, CTEs
   +1300 XP
4. 4
   Senior Senior

   Indexing, query plans, tuning
   +2500 XP
5. 5
   Architect Architect

   Sharding, replication, OLAP
   +4100 XP
6. 6
   Legend Legend

   Contribute a challenge
   +6100 XP

Challenge types

Open challenges

• Easy Rookie SpeedRun

  SQL: Counting INNER JOIN Rows

  +100 XP · 6 min · joins, inner-join, fundamentals
• Medium Apprentice SpeedRun

  SQL: COUNT, COUNT(*), and NULLs

  +180 XP · 5 min · aggregates, null, count
• Medium Apprentice SpeedRun

  SQL: RANK() With Ties

  +200 XP · 8 min · window-functions, rank, analytics
• Medium Engineer SpeedRun

  SQL: WHERE vs HAVING

  +200 XP · 8 min · group-by, having, aggregation
• Hard Engineer SpeedRun

  SQL: NOT IN With NULL Returns Nothing

  +220 XP · 6 min · null, three-valued-logic, subqueries

Badges earned