### Database Schema:
CREATE TABLE location (
	id_restaurant	INTEGER	NOT NULL	PRIMARY KEY,
	street_num	INTEGER	NULL,
	street_name	TEXT	NULL,
	city	TEXT	NULL,
	foreign key (city) references geographic (city),
	foreign key (id_restaurant) references generalinfo (id_restaurant)
);

CREATE TABLE geographic (
	city	TEXT	NOT NULL	PRIMARY KEY,
	county	TEXT	NULL,
	region	TEXT	NULL
);

CREATE TABLE generalinfo (
	id_restaurant	INTEGER	NOT NULL	PRIMARY KEY,
	label	TEXT	NULL,
	food_type	TEXT	NULL,
	city	TEXT	NULL,
	review	REAL	NULL,
	foreign key (city) references geographic (city)
);

### User's Query:
In which streets of the city of San Francisco are there restaurants that serve seafood?

### Extra Knowledge:
street refers to street_name; seafood refers to food_type = 'seafood'
SELECT T1.street_name FROM location AS T1 INNER JOIN generalinfo AS T2 ON T1.id_restaurant = T2.id_restaurant WHERE T1.city = 'san francisco' AND T2.food_type = 'seafood' AND street_name IS NOT NULL