### 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:
Calculate the average rating of reviews for restaurants in Santa Cruz County.

### Extra Knowledge:
average rating = divide(sum(review where county = 'santa cruz county'), count(id_restaurant where county = 'santa cruz county'))
SELECT AVG(T2.review) FROM geographic AS T1 INNER JOIN generalinfo AS T2 ON T1.city = T2.city WHERE T1.county = 'santa cruz county'