CREATE TABLE reservations (code DECIMAL, room TEXT, checkin TEXT, checkout TEXT, rate DECIMAL, lastname TEXT, firstname TEXT, adults DECIMAL, kids DECIMAL)
CREATE TABLE rooms (roomid TEXT, roomname TEXT, beds DECIMAL, bedtype TEXT, maxoccupancy DECIMAL, baseprice DECIMAL, decor TEXT)

What kind of decor has the least number of reservations?
SELECT T2.decor FROM reservations AS T1 JOIN rooms AS T2 ON T1.room = T2.roomid GROUP BY T2.decor ORDER BY COUNT(T2.decor) LIMIT 1
SELECT "T2"."decor" FROM "reservations" AS "T1" JOIN "rooms" AS "T2" ON "T1"."room" = "T2"."roomid" GROUP BY "T2"."decor" ORDER BY COUNT("T2"."decor") NULLS FIRST LIMIT 1