### Database Schema:
CREATE TABLE race (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	race	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE attribute (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	attribute_name	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE alignment (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	alignment	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE hero_power (
	hero_id	INTEGER	NULL	DEFAULT NULL,
	power_id	INTEGER	NULL	DEFAULT NULL,
	foreign key (hero_id) references superhero (id),
	foreign key (power_id) references superpower (id)
);

CREATE TABLE colour (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	colour	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE gender (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	gender	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE hero_attribute (
	hero_id	INTEGER	NULL	DEFAULT NULL,
	attribute_id	INTEGER	NULL	DEFAULT NULL,
	attribute_value	INTEGER	NULL	DEFAULT NULL,
	foreign key (hero_id) references superhero (id),
	foreign key (attribute_id) references attribute (id)
);

CREATE TABLE publisher (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	publisher_name	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE superpower (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	power_name	TEXT	NULL	DEFAULT NULL
);

CREATE TABLE superhero (
	id	INTEGER	NOT NULL	PRIMARY KEY,
	superhero_name	TEXT	NULL	DEFAULT NULL,
	full_name	TEXT	NULL	DEFAULT NULL,
	gender_id	INTEGER	NULL	DEFAULT NULL,
	eye_colour_id	INTEGER	NULL	DEFAULT NULL,
	hair_colour_id	INTEGER	NULL	DEFAULT NULL,
	skin_colour_id	INTEGER	NULL	DEFAULT NULL,
	race_id	INTEGER	NULL	DEFAULT NULL,
	publisher_id	INTEGER	NULL	DEFAULT NULL,
	alignment_id	INTEGER	NULL	DEFAULT NULL,
	height_cm	INTEGER	NULL	DEFAULT NULL,
	weight_kg	INTEGER	NULL	DEFAULT NULL,
	foreign key (gender_id) references gender (id),
	foreign key (hair_colour_id) references colour (id),
	foreign key (publisher_id) references publisher (id),
	foreign key (race_id) references race (id),
	foreign key (eye_colour_id) references colour (id),
	foreign key (alignment_id) references alignment (id),
	foreign key (skin_colour_id) references colour (id)
);

### User's Query:
How many percent of female heroes were published by Marvel Comics?

### Extra Knowledge:
percent = MULTIPLY(DIVIDE(SUM(gender = 'Female' WHERE publisher_name = 'Marvel Comics'), COUNT(publisher_name = 'Marvel Comics')), 100); female heroes refers to gender = 'Female'; Marvel Comics refers to publisher_name = 'Marvel Comics';
SELECT CAST(COUNT(CASE WHEN T2.publisher_name = 'Marvel Comics' THEN 1 ELSE NULL END) AS REAL) * 100 / COUNT(T1.id) FROM superhero AS T1 INNER JOIN publisher AS T2 ON T1.publisher_id = T2.id INNER JOIN gender AS T3 ON T1.gender_id = T3.id WHERE T3.gender = 'Female'