Name the purpose for on-air ID of 2xx
CREATE TABLE "defunct_callsigns" (
  "callsign" text,
  "area_served" text,
  "frequency" text,
  "band" text,
  "on_air_id" text,
  "purpose" text
);
SELECT "purpose" FROM "defunct_callsigns" WHERE "on_air_id"='2xx';