CREATE TABLE table_47434 ("Year" FLOAT, "Award" CLOB, "Category" CLOB, "Nominated work" CLOB, "Result" CLOB)

How many years had the best actress in a Revival category?
SELECT COUNT("Year") FROM table_47434 WHERE "Category" = 'best actress in a revival'
SELECT COUNT("Year") FROM "table_47434" WHERE "Category" = 'best actress in a revival'