CREATE TABLE song (song_name TEXT, artist_name TEXT, country TEXT, f_id DECIMAL, genre_is TEXT, rating DECIMAL, languages TEXT, releasedate TIME, resolution DECIMAL)
CREATE TABLE artist (artist_name TEXT, country TEXT, gender TEXT, preferred_genre TEXT)
CREATE TABLE files (f_id DECIMAL, artist_name TEXT, file_size TEXT, duration TEXT, formats TEXT)
CREATE TABLE genre (g_name TEXT, rating TEXT, most_popular_in TEXT)

How many songs, on average, are sung by a female artist?
SELECT AVG(T2.rating) FROM artist AS T1 JOIN song AS T2 ON T1.artist_name = T2.artist_name WHERE T1.gender = "Female"
SELECT AVG("T2"."rating") FROM "artist" AS "T1" JOIN "song" AS "T2" ON "T1"."artist_name" = "T2"."artist_name" WHERE "Female" = "T1"."gender"