Question: What is the McCune-Reischauer when the 2000 n South Korea population * is more than 6796227 people, and a Hangul of 송?
SQL: SELECT "McCune-Reischauer" FROM "2-15838180-1" WHERE "2000 n South Korea population *" > 6796227.0 AND "Hangul" = '송';

Question: What is the Hanja for McCune-Reischauer of Chŏn?
SQL: SELECT "Hanja" FROM "2-15838180-1" WHERE "McCune-Reischauer" = 'Chŏn';

Question: What is the Hangul when the Hanja is 西, 徐?
SQL: SELECT "Hangul" FROM "2-15838180-1" WHERE "Hanja" = '西, 徐';