CREATE TABLE table_26914854_3 (incoming_manager VARCHAR2, date_of_vacancy VARCHAR2)

Who is the incoming manager when the date of vacancy was 21 march 2011?
SELECT incoming_manager FROM table_26914854_3 WHERE date_of_vacancy = "21 March 2011"
SELECT "incoming_manager" FROM "table_26914854_3" WHERE "21 March 2011" = "date_of_vacancy"