CREATE TABLE table_203_60 (id NUMBER, "outcome" CLOB, "no." NUMBER, "date" CLOB, "championship" CLOB, "surface" CLOB, "opponent in the final" CLOB, "score in the final" CLOB)

which surface was used the least ?
SELECT "surface" FROM table_203_60 GROUP BY "surface" ORDER BY COUNT("surface") LIMIT 1
SELECT "surface" FROM "table_203_60" GROUP BY "surface" ORDER BY COUNT("surface") FETCH FIRST 1 ROWS ONLY