CREATE TABLE wedding (church_id VARCHAR, year VARCHAR)
CREATE TABLE church (name VARCHAR)

Show all church names except for those that had a wedding in year 2015.
SELECT name FROM church EXCEPT SELECT T1.name FROM church AS T1 JOIN wedding AS T2 ON T1.church_id = T2.church_id WHERE T2.year = 2015
SELECT "name" FROM "church" EXCEPT SELECT "T1"."name" FROM "church" AS "T1" JOIN "wedding" AS "T2" ON "T1"."church_id" = "T2"."church_id" AND "T2"."year" = 2015