SQL 4 Done

[Aniruddh-2512]

No description provided.

[super30admin]

1. Correctness:

   • FriendRequests2.sql: The solution correctly identifies the person with the most friend requests by counting both requester and accepter IDs. This approach is correct for finding the most popular person.
   • LeagueStatistics.sql: The solution accurately calculates team statistics including points, goals for, goals against, and goal difference. The UNION ALL approach for home and away matches is correct.
   • NumberofSeniors.sql: The solution correctly calculates the number of senior and junior candidates that can be hired within a budget, using window functions to track cumulative sums.
   • SalesPerson.sql: The solution correctly identifies salespersons who didn't sell to company 'RED' using a NOT IN clause with a subquery.

2. Time Complexity:

   • All solutions appear to have reasonable time complexity for their respective problems, primarily O(n) or O(n log n) due to sorting and grouping operations.

3. Space Complexity:

   • The space complexity is generally efficient, with temporary tables (CTEs) being used appropriately to organize intermediate results.

4. Code Quality:

   • The code is generally well-structured and readable.
   • Consistent use of CTEs improves readability.
   • Some queries could benefit from more descriptive column aliases (e.g., 'num' in FriendRequests2.sql could be 'friend_count').
   • The NumberofSeniors.sql query could be simplified by using a single CTE with conditional aggregation.

5. Efficiency:

   • FriendRequests2.sql: The solution is efficient, but could potentially be optimized by using COUNT(*) instead of COUNT(id) since id is guaranteed to be non-null.
   • LeagueStatistics.sql: The solution is already quite efficient.
   • NumberofSeniors.sql: The solution could be made more efficient by combining the senior and junior calculations into a single pass.
   • SalesPerson.sql: The solution is efficient, but could be written using NOT EXISTS instead of NOT IN for potentially better performance with NULL values.