Table: chess_players_comparison
Columns: position
best_year
best_2_year_period
best_3_year_period
best_5_year_period
best_10_year_period
best_15_year_period

Question: Which people had the best 10-year period when Fischer had best 15-year period?
SQL: SELECT "best_10_year_period" FROM chess_players_comparison WHERE "best_15_year_period" = 'Fischer'

Question: Which people had the best 10-year period when Capablanca had the best 15-year period?
SQL: SELECT "best_10_year_period" FROM chess_players_comparison WHERE "best_15_year_period" = 'Capablanca'