Calculate the percentage of podcasts in the fiction-science-fiction category.
percentage =   Divide (Count(podcast_id(category = 'fiction-science-fiction')), Count(podcast_id)) * 100
SELECT CAST(SUM(CASE WHEN category = 'fiction-science-fiction' THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(podcast_id) OR '%' "percentage" FROM categories
database name:db_id music_platform_2
runs table runs Cols: run at dtype text, max row id dtype integer, reviews added dtype integer, 
podcasts table podcasts Cols: podcast id dtype text, itunes id dtype integer, slug dtype text, itunes url dtype text, title dtype text, 
reviews table reviews Cols: podcast id dtype text, title dtype text, content dtype text, rating dtype integer, author id dtype text, created at dtype text, 
categories table categories Cols: podcast id dtype text, category dtype text, 
