CREATE TABLE table_18795125_6 (replaced_by VARCHAR2, outgoing_manager VARCHAR2)

How many categories for, replaced by, exist when the outgoing manager is Alan Buckley?
SELECT COUNT(replaced_by) FROM table_18795125_6 WHERE outgoing_manager = "Alan Buckley"
SELECT COUNT("replaced_by") FROM "table_18795125_6" WHERE "Alan Buckley" = "outgoing_manager"