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CREATE TABLE users(user_id int, name varchar(100));
INSERT INTO users(user_id, name) VALUES
(10, 'Bob'), (20, 'Jeff');
CREATE TABLE cities(city_id int, name varchar(100));
INSERT INTO cities(city_id, name) VALUES
(100, 'New York'), (200, 'Boston');
4 rows affected
CREATE TABLE users_countries(user_id int, city_id int);
INSERT INTO users_countries(user_id, city_id) VALUES
(
(
SELECT TOP 1 user_id FROM users
WHERE name = 'Jeff'
),
(
SELECT TOP 1 city_id FROM cities
WHERE name = 'Boston'
)
);
1 rows affected
SELECT * FROM users_countries;
| user_id | city_id |
|---|---|
| 20 | 200 |