SQL Reference Keywords

SELECT * FROM employees;

SELECT name FROM employees;

SELECT * FROM employees WHERE age > 30;

SELECT * FROM employees JOIN departments ON employees.dept_id = departments.id;

SELECT dept_id, COUNT(*) FROM employees GROUP BY dept_id;

SELECT * FROM employees ORDER BY name ASC;

INSERT INTO employees (name, age, dept_id) VALUES ('John Doe', 28, 2);

UPDATE employees SET age = 29 WHERE name = 'John Doe';

DELETE FROM employees WHERE id = 1;

CREATE TABLE employees (id INT PRIMARY KEY, name VARCHAR(100), age INT);

ALTER TABLE employees ADD COLUMN salary DECIMAL(10, 2);

DROP TABLE employees;

CREATE INDEX idx_name ON employees (name);

CREATE VIEW employee_view AS SELECT * FROM employees WHERE age > 30;

TRUNCATE TABLE employees;

GRANT SELECT ON employees TO user_name;

REVOKE SELECT ON employees FROM user_name;

COMMIT;

ROLLBACK;

SELECT DISTINCT dept_id FROM employees;

SELECT * FROM employees WHERE name LIKE 'J%';

SELECT * FROM employees WHERE salary IS NULL;

SELECT * FROM employees WHERE age > 25 AND dept_id = 1;

SELECT * FROM employees WHERE age < 25 OR dept_id = 1;

SELECT * FROM employees WHERE NOT dept_id = 1;

SELECT * FROM employees WHERE age BETWEEN 25 AND 35;

SELECT * FROM employees WHERE dept_id IN (1, 2, 3);

SELECT * FROM employees WHERE EXISTS (SELECT * FROM departments WHERE id = employees.dept_id);

SELECT dept_id, COUNT(*) FROM employees GROUP BY dept_id HAVING COUNT(*) > 5;

SELECT name, CASE WHEN age < 20 THEN 'Teen' WHEN age < 60 THEN 'Adult' ELSE 'Senior' END AS age_group FROM employees;

SELECT COALESCE(salary, 0) FROM employees;

SELECT CAST(age AS VARCHAR(3)) FROM employees;

SELECT CONVERT(VARCHAR(10), salary) FROM employees;

SELECT name AS employee_name FROM employees;

SELECT * FROM employees INNER JOIN departments ON employees.dept_id = departments.id;

SELECT * FROM employees LEFT JOIN departments ON employees.dept_id = departments.id;

SELECT * FROM employees RIGHT JOIN departments ON employees.dept_id = departments.id;

SELECT * FROM employees FULL OUTER JOIN departments ON employees.dept_id = departments.id;

SELECT * FROM employees CROSS JOIN departments;