CREATE TABLE bridge (architect_id NUMBER, id NUMBER, name CLOB, location CLOB, length_meters NUMBER, length_feet NUMBER)
CREATE TABLE architect (id CLOB, name CLOB, nationality CLOB, gender CLOB)
CREATE TABLE mill (architect_id NUMBER, id NUMBER, location CLOB, name CLOB, type CLOB, built_year NUMBER, notes CLOB)

What are the distinct types of mills that are built by American or Canadian architects?
SELECT DISTINCT T1.type FROM mill AS T1 JOIN architect AS t2 ON T1.architect_id = T2.id WHERE T2.nationality = 'American' OR T2.nationality = 'Canadian'
SELECT DISTINCT "T1"."type" FROM "mill" "T1" JOIN "architect" "t2" ON "T1"."architect_id" = "T2"."id" WHERE "T2"."nationality" = 'American' OR "T2"."nationality" = 'Canadian'