系统权限、角色和对象权限的授了都要遵循最小化使用原则。单选()
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从student表中查询学生姓名、年龄和成绩,结果按照年龄降序排序,年龄相同的按照成绩升序排序,下面SQL语句正确的是?()
A. select name, age, score from student order by age desc , score;
B. select name, age, score from student order by age , score asc;
C. select name, age, score from student order by 2 desc , 3 asc;
D. select name, age, score from student order by 1 desc , 2 ;
GaussDB100是款完全自研的交易型数据库。单选()
A. TRUE
B. FALSE
现有员工表A,包含员Iidstatfjd)和部门id(sectionjd)两李段部门表B.包含部门id(section,id)和部所在城市(ity)两字段,若想要查询该公司每个城市的员工数以下语句可以实现的是?单选()
A. select city, count(staff_id) from AjoinB on A.section_id = B. section_id group by B. section:
B. select city, count(staff id) from A.B group by city;
C. selet city,count(staff_id) from A join B where A.section_id=B. section_id group by city;
D. select city.count(staff_id) from A join B on A.section_id = B.section_id group by city
实体之间的识别性关系也可以发生在两个独立实体之间。单选()
A. TRUE
B. FALSE