CREATE TABLE table_21666472_1 (no_in_series VARCHAR2, written_by VARCHAR2)

How many number in series's are written by Greg Haddrick?
SELECT COUNT(no_in_series) FROM table_21666472_1 WHERE written_by = "Greg Haddrick"
SELECT COUNT("no_in_series") FROM "table_21666472_1" WHERE "Greg Haddrick" = "written_by"