CREATE TABLE table_name_34 (manufacturer VARCHAR2, wheel_arrangement VARCHAR2, class VARCHAR2)

What manufacturer has a wheel arrangement of 4-6-6-4, and a Class of z-7?
SELECT manufacturer FROM table_name_34 WHERE wheel_arrangement = "4-6-6-4" AND class = "z-7"
SELECT "manufacturer" FROM "table_name_34" WHERE "4-6-6-4" = "wheel_arrangement" AND "class" = "z-7"