Question

我有Table1，它有一个名为员工编号的列，我想根据具体范围对其进行分类例如：

id  employeeNumber
1    0
1    50
2    100
3    500
4    1000

我希望结果是这样的，例如，如果有多少员工来自 0到100它会落在C1中， 500到1000将落在C2 ..等等

Answer 1

您可以使用case：

select t1.id,
       (case when employeenumber between 0 and 100 then 'C1'
             when employeenumber between 500 and 1000 then 'C2'
        end) as en_range
from table1 t1;

您似乎没有101-499的范围。

Answer 2

使用像

这样的CASE语句

SELECT 
    CASE 
    WHEN employeeNumber BETWEEN 0 AND 100 THEN 'C1' 
    WHEN employeeNumber BETWEEN 101 AND 500 THEN 'C2' 
END as employeeCode FROM table

Answer 3

有几种方法可以做到这一点，这取决于您想要使用相同分组的频率。如果这是一次性的，我建议这样的事情（我不确定你的类别似乎不是连续的）：

SELECT
    id,
    case
        when employeeNumber <= 100 then 'C1'
        when employeeNumber <= 500 then 'C2'
        /* etc, the first match will be used so no need to worry about missing '>='s */
        else 'Uncategorized' -- or if your final category has no upper limit, you could put that here, but be careful of `NULL`s as employeeNumber seems not to be a primary key field.
    end as Category
FROM
    Table1

如果要重复使用这些类别，请按如下方式创建表：

create table EmployeeCategories(
Category varchar(3), --Or whatever data type you need. You could also add extra columns to describe the category if that's helpful.
LowerBound int,
UpperBound int
)

用您的分组填充它：

insert into EmployeeCategories
       (Category, LowerBound, UpperBound)
values ('C1', 0, 100),
       ('C2', 101, 1000)
       /* Etc */

对于最终类别，如果没有最大值，您可以离开UpperBound NULL。然后你这样做：

SELECT
    t.id,
    ec.Category
FROM
    Table1 t
    CROSS JOIN EmployeeCategories ec
WHERE
    t.employeeNumber between ec.LowerBound and ec.UpperBound
    OR (t.employeeNumber >= ec.LowerBound and ec.UpperBound is null)

如何对数字列进行分类

3 个答案: