mysql实现每个专业分数段统计人数

student_info

| id |name |profession|score|

|--|--|--|--|

|id|姓名|分数|专业|

select

count(case when score between 400 and 500 then 1 end) as 400到500,

count(case when score between 300 and 400 then 1 end) as 300到400

from student_info;

select

count(case when score between 400 and 500 then 1 end) as 400到500,

count(case when score between 300 and 400 then 1 end) as 300到400

from student_info GROUP BY profession;

int start = 200;

      int end = 700;

      int inter = 10;

      int count = (end-start)/inter;

      StringBuilder sqlBuilder = new StringBuilder();

      sqlBuilder.append("select ");

      for(int i =1;i<=count;i++){

          int next = start+inter-1;

          System.out.println(start + " \t" + next);

          sqlBuilder.append(" count(case when admission_score between ").append(start).append(" and ").append(next).append(" then 1 end) as ").append(start).append("到").append(next);

          if(i!=count){

              sqlBuilder.append(", ");

          }

          start += inter;

      }

      sqlBuilder.append(" from z_student_info");

      System.out.println(sqlBuilder.toString());