CREATE TABLE table_54651 ("Race Name" CLOB, "Circuit" CLOB, "Date" CLOB, "Winning driver" CLOB, "Constructor" CLOB, "Report" CLOB)

Who is the constructor whose circuit was Oulton Park?
SELECT "Constructor" FROM table_54651 WHERE "Circuit" = 'oulton park'
SELECT "Constructor" FROM "table_54651" WHERE "Circuit" = 'oulton park'