数据库嵌套查询例题 下列哪个查询语句使用了嵌套查询来找出工资高于公司平均工资的员工? A. SELECT * FROM employees WHERE salary > AVG(salary); B. SELECT * FROM employees WHERE salary > (SELECT AVG(salary) FROM employees); C. SELECT * FROM employees, (SELECT AVG(salary) FROM employees) AS avg...