Question

需要查询以获取项目名称以及分配了项目的员工各自的名字。如果在给定的项目下有多个员工，则第二列应将所有名称用逗号。例如：Vikash，Ashish。

我有两个表：

Table1: EmployeeID, FirstName

1 Vikas
2 nikita
3 Ashish
4 Nikhil
5 anish

Table2: EmployeeDetailID, ProjectName
1|Task Track
1|CLP
1|Survey Managment
2|HR Managment
3|Task Track
3|GRS
3|DDS
4|HR Managment
6|GL Managment

我使用以下代码获取员工的姓名和他们正在从事的项目：

select  FirstName, ProjectName
from EmployeeInfo, EmployeeProjects
where EmployeeID = EmployeeDetailID;

输出：

Vikas Task Track
Vikas CLP
Vikas Survey Managment
nikita HR Managment
Ashish Task Track
Ashish GRS
Ashish DDS
Nikhil HR Managment

我不知道如何组合多行并使用逗号分隔它们。

Answer 1

也许使用在listagg之类的组上运行的串联功能：

select Table2.ProjectName, listagg(Table1.FirstName, ', ')
within group (order by Table1.FirstName) as members
from Table1, Table2
where Table1.EmployeeID = Table2.EmployeeDetailID
group by Table2.ProjectName

Answer 2

尝试一下：

SELECT
    T2.PROJECTNAME,
    RTRIM(XMLAGG(XMLELEMENT(E, T1.FIRSTNAME, ',').EXTRACT('//text()')
        ORDER BY
            T1.FIRSTNAME
    ).GETCLOBVAL(), ',') AS MEMBERS
FROM
    TABLE1 T1
    JOIN TABLE2 T2 ON ( T1.EMPLOYEEID = T2.EMPLOYEEDETAILID )
GROUP BY
    T2.PROJECTNAME;

如果您的合并字符串的长度超过4000个字符，

LISTAGG将引发错误。

将多行汇总为单行

2 个答案: