CREATE TABLE table_203_197 (id NUMBER, "#" NUMBER, "title" CLOB, "artist" CLOB, "highest pos. reached" NUMBER, "weeks at no. 1" CLOB)

which song stayed at no. 1 for the most amount of weeks .
SELECT "title" FROM table_203_197 ORDER BY "weeks at no. 1" DESC LIMIT 1
SELECT "title" FROM "table_203_197" ORDER BY "weeks at no. 1" DESC FETCH FIRST 1 ROWS ONLY