将student表按照gender列值进行分组查询,并计算出每个分组中各有多少名学生,正确SQL语句是( )。
A. SELECT TOTAL(*),gender FROM student GROUP BY gender
B. SELECT COUNT(*),gender FROM student GROUP BY gender
C. SELECT TOTAL(*),gender FROM student ORDER BY gender
D. SELECT COUNT(*),gender FROM student ORDER BY gender
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从Student中查询出各专业学生的入学录取平均分,显示“专业”和“平均分”两列,保留一位小数。SELECT Specialty AS ① ,平均分=str( ② (AScores),5,1)FROM StudentGROUP BY ③
从Student中查询出各专业的学生总数,结果显示“专业”和“人数”两列。SELECT 专业=Specialty,人数= ①FROM Student② BY Specialty
从SC中统计出每位学生的总成绩,显示学号、姓名和“总成绩”。SELECT SC.SID, Sname,'总成绩'=① (Scores)FROM ②,StudentWHERE SC.③=Student.SIDGROUP BY ④, Sname
查询每一个专业中,男女生各自的人数。SELECT Specialty,Sex,COUNT(*) AS 人数FROM StudentGROUP BY ①,②