mysql数据库试题及答案
@时轻1478：求MySQL数据库选择题答案 -
巢凭19884192754…… select `stu_id`,avg(`grade`),sum(`grade` < 60) as num from score group by `stu_id` having num >=2' avg(`grade`):求平均值 sum(`grade` < 60) :统计小于六十分的个数 group by `stu_id` :按照uid统计 having num >=2:判断统计的个数大于2
@时轻1478：mysql基础题目解答 -
巢凭19884192754…… 1. SELECT TITLE,SUBTITLE,ISBN FROM TITLES;2. SELECT MAX(authID),MIN(authID),AVG(authID),COUNT(authID) FROM authors3. SELECT COUNT(DISTINCT AUTHID) FROM AUTHORS4. ALTER TABLE LANGUAGES ADD TEMP INT ...
巢凭19884192754…… select `stu_id`,avg(`grade`),sum(`grade` < 60) as num from score group by `stu_id` having num >=2' avg(`grade`):求平均值 sum(`grade` < 60) :统计小于六十分的个数 group by `stu_id` :按照uid统计 having num >=2:判断统计的个数大于2
@时轻1478：mysql基础题目解答 -
巢凭19884192754…… 1. SELECT TITLE,SUBTITLE,ISBN FROM TITLES;2. SELECT MAX(authID),MIN(authID),AVG(authID),COUNT(authID) FROM authors3. SELECT COUNT(DISTINCT AUTHID) FROM AUTHORS4. ALTER TABLE LANGUAGES ADD TEMP INT ...
