CREATE TABLE "managerial_changes" (
  "team" text,
  "outgoing_manager" text,
  "manner_of_departure" text,
  "date_of_vacancy" text,
  "last_match" text,
  "replaced_by" text
);

Question: Name the total number of date of vacancy for manner of departure being resigned and outgoing manager is geninho
SQL: SELECT COUNT("date_of_vacancy") FROM "managerial_changes" WHERE "manner_of_departure"='Resigned' AND "outgoing_manager"='Geninho';