Who won the men's singles in 1958?
CREATE TABLE "canadian_national_championships_and_cana" (
  "year" real,
  "men_s_singles" text,
  "women_s_singles" text,
  "men_s_doubles" text,
  "women_s_doubles" text,
  "mixed_doubles" text
);
SELECT "men_s_singles" FROM "canadian_national_championships_and_cana" WHERE "year"=1958;