综合训练 1

select * users 5;

TABLE users ( id INT NOT NULL, AUTO_INCREMENT, username (55), password VARCHAR(55) );

SELECT * FROM customers balance >500 city='New York' 50;

SELECT * FROM customers balance > 500 city='New York' 50;

• UNION
• WHERE animal IN ('bear'
• 'bird')
• WHERE animal IN ('lion'
• 'crocodile');
• SELECT age FROM zoo2
• SELECT age FROM zoo1

SELECT (name, ' is from ',) FROM customers;

• (SELECT AVG(age)
• SELECT * FROM zoo
• WHERE age >
• FROM zoo);

SELECT age FROM students WHERE name LIKE '  s';