A: by number
B: from number
C: by my count
D: from count
举一反三
- 阅读以下程序public class Count{static int count;int number;public Count(){count = count + 1;number = count;}}class Test{public static void Main(){Count a = new Count();Count b = new Count();Count c = new Count();}}程序运行后，对象a的count值是（） A: 0 B: 1 C: 2 D: 3
- 查询选修了2门课程以上的学生学号（） A: select sid,count(*) from sc group by sid having count(*)>=2 B: select sid,count(*) from sc group by sid where count(*)>=2 C: select sid,count(*) from sc where count(*)>=2 group by sid D: select sid,count(*) from sc group by cid having count(*)>=2
- 以下哪条语句可以实现查询选了课的学生人数（ ）。 A: select count(*) from sc B: select count(sno) from sc C: select count(distinct sno) from sc D: select count(cno) from sc
- According to the passage, what did small children do when they were asked to count a pile of red and blue pencils A: a. They counted the number of pencils of each color. B: b. They guessed at the total number of pencils. C: c. They counted only the pencils of their favorite color. D: d. They subtracted the number of red pencils from the number of blue pencils.
- select count(*) from 表名 group by count(*)
内容
- 0
select count(*) from 表名 having count(*)>;2
- 1
若需统计“选课”表中已经选修了课程的学生人数，下面语句正确的是( )。 A: SELECT COUNT(DISTINCT学生号)FROM选课 B: SELECT COUNT(学生号)FROM选课 C: SELECT COUNT(*)FROM选课 D: SELECT COUNT(DISTINCT*)FROM选课
- 2
按课程号分类，统计相应的选课人数（） A: select cid, count(distinct sid) from sc group by cid B: select cid, count(*) from student group by cid C: select cid, count(distinct cid) from sc group by cid D: select cid, count(distinct sid) from student group by cid
- 3
(Short-answer Question)What transitional states are possible when a 4-bit asynchronous binary counter changes from (a) count 2 to count 3 (b) count 3 to count 4 (c) count 1010 to count 1110 (d) count 15 to count 0
- 4
查询scott用户的emp表中的总记录数,可以使用下列哪个语句?() A: SELECT MAX(empno) FROM scott.emp; B: SELECT<br/>COUNT(empno) FROM scott.emp; C: SELECT COUNT(comm) FROM scott.emp; D: SELECT COUNT(*) FROM scott.emp;