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

which three artists had a single at number 1 for at least 7 weeks on the australian singles charts in 1977 ?
SELECT "artist" FROM table_203_197 WHERE "weeks at no. 1" >= 7
SELECT "artist" FROM "table_203_197" WHERE "weeks at no. 1" >= 7