Concatenate Multiple Columns into Single

Question

Hi All,
I am developing a report and there is a field called FUNDING_SOURCE.
This field is being picked from class_code of PA_PROJECT_CLASSES table as shown below:
(select distinct(class_code)
from pa_project_classes ppc,
pa_projects_all ppa
where class_category = 'FUNDING SOURCE'
and ppc.project_id = :project_id)
But, the requirement is to have all values of Funding Source for a particular project ID concatenated into a single column.
Eg: If I run the above code, the output would be in 3 rows,
Intenal
External
Other
I want the output concatenated and displayed as Internal, External, Other.
Please help me ASAP. Need to finish this soon.
Thanks!

Answer 1

                    SELECT substr(MAX(sys_connect_by_path(a,
                                                          '~')),
                                  2) --first character wil be ~ max is used because the query will return 3 rows and u need only one row with all values appended
                      FROM (SELECT a,
                                   row_number() over(ORDER BY t.b) AS curr, --order in which appending happens
                                   row_number() over(ORDER BY t.b) - 1 AS prev --order in which appending happens
                              FROM (SELECT 'Internal' a,
                                           1 b
                                      FROM dual
                                    UNION ALL
                                    SELECT 'External' a,
                                           2 b
                                      FROM dual
                                    UNION ALL
                                    SELECT 'Other' a,
                                           3 b
                                      FROM dual) t --creating dummy table
                    CONNECT BY prev = PRIOR curr
                     START WITH curr = 1;