Completed Mock-SQL-3

[Paneripatel]

No description provided.

[super30admin]

1. Correctness:

   • For MarketAnalysisII.sql, the solution correctly identifies the second item sold by each seller and checks if it matches their favorite brand. However, it doesn't handle cases where a seller has less than 2 orders (LEFT JOIN will return NULL for item_brand, which is correctly handled by the IF statement).
   • For TournamentWinners.sql, the solution correctly calculates the total score for each player and ranks them within their group. The tie-breaker (player_id ASC) is appropriately implemented.

2. Time Complexity:

   • MarketAnalysisII.sql: O(n log n) due to the RANK() window function and JOIN operations.
   • TournamentWinners.sql: O(n log n) due to the RANK() window function and GROUP BY operations.

3. Space Complexity:

   • Both solutions use temporary storage for CTEs/intermediate tables, resulting in O(n) space complexity.

4. Code Quality:

   • Both solutions are well-structured with clear CTE naming (CTE, ACTE) and proper indentation.
   • The SQL keywords are consistently capitalized.
   • The column alias "2nd_item_fav_brand" in MarketAnalysisII.sql should be quoted or renamed to avoid syntax issues (numbers can't start unquoted identifiers in some SQL dialects).
   • The JOIN condition in TournamentWinners.sql (p.player_id IN (m.first_player, m.second_player)) is correct but could be more explicit with OR conditions for clarity.

5. Efficiency:

   • Both solutions are efficient for their respective problems.
   • For MarketAnalysisII.sql, adding a WHERE clause to filter out sellers with less than 2 orders before the RANK() operation could potentially improve performance.
   • For TournamentWinners.sql, the solution is already optimal.

[super30admin]

1. Correctness:

   • For MarketAnalysisII.sql, the solution correctly identifies the second item sold by each seller and checks if it matches their favorite brand. However, it doesn't handle cases where a seller has fewer than 2 orders (they will be left with NULL in the result).
   • For TournamentWinners.sql, the solution correctly calculates the total scores for each player and ranks them within their groups. The tie-breaker (player_id) is appropriately handled.

2. Time Complexity:

   • MarketAnalysisII.sql: O(n log n) due to the RANK() window function and JOIN operations.
   • TournamentWinners.sql: O(n log n) due to the GROUP BY, SUM, and RANK() operations.

3. Space Complexity:

   • Both solutions use temporary storage for CTEs/intermediate results, resulting in O(n) space complexity.

4. Code Quality:

   • Both solutions are well-structured with clear CTE usage.
   • Naming conventions are good (CTE, ACTE, intermediate).
   • The SQL is readable with proper indentation and spacing.
   • One minor issue: in MarketAnalysisII.sql, the column alias "2nd_item_fav_brand" should be quoted or renamed to avoid using numbers at the start.

5. Efficiency:

   • MarketAnalysisII.sql could be improved by handling sellers with fewer than 2 orders more explicitly (perhaps with COALESCE or explicit NULL handling).
   • TournamentWinners.sql is already quite efficient, though the JOIN condition could be written more clearly as (p.player_id = m.first_player OR p.player_id = m.second_player).