使用Oracle SQL进行检查的座位安排

Question

我正在尝试从下面的数据集中安排考试的位置。

，输出数据集如下所示（另一系学生一个接一个）

我无法获得愿望输出。请帮我。我正在使用Oracle 11g速成版。

http://sqlfiddle.com/#!4/510071/1

Answer 1

使用ROW_NUMBER分析函数，为每个部门创建排序顺序；然后选择按该数字排序的值。

例如：

SQL> with test (roll_no, name, department) as
  2    (select  1, 'anik',    'cse' from dual union all
  3     select  2, 'sudipto', 'cse' from dual union all
  4     select  3, 'injamam', 'cse' from dual union all
  5     select  8, 'sajukta', 'ece' from dual union all
  6     select  9, 'gourab',  'ece' from dual union all
  7     select 10, 'soumenn', 'ece' from dual),
  8  inter as
  9    (select roll_no, name, department,
 10       row_number() over (partition by department order by roll_no) rn
 11     from test
 12    )
 13  select roll_no, name, department
 14  from inter
 15  order by rn, department;

   ROLL_NO NAME    DEP
---------- ------- ---
         1 anik    cse
         8 sajukta ece
         2 sudipto cse
         9 gourab  ece
         3 injamam cse
        10 soumenn ece

6 rows selected.

SQL>

Answer 2

您似乎希望它们交错。如果是这样，请在row_number()中使用order by：

select s.*
from student s
order by row_number() over (partition by "department" order by "roll_no"),
         "department";

Here是SQL Fiddle。

注意：不要将列名用双引号引起来。这意味着标识符的大小写很重要-只会使查询难以编写。