在循环输出 Oracle PLSQL 函数时需要帮助

Question

我目前正在研究 oracle PLSQL 功能，以列出项目编号、职位和参与每个项目的员工姓名。到目前为止，我能够获得所需的输出，但只能在一个一个调用之后才能做到。如何在我的代码中实现一个循环以允许它一次调用它。

[当前代码]

create or replace procedure PROJECTGROUPS(projectid IN WorksOn.P#%TYPE)
IS
PID Project.P#%TYPE;
PNAME Project.PTitle%TYPE;
ENAME Employee.Name%TYPE;
finalRow VARCHAR(2000);
CURSOR query is
select Employee.Name from Employee
left outer join WorksOn On Employee.E# = WorksOn.E#
where WorksOn.P# = projectid
order by Employee.Name ASC
fetch first 20 rows only;
--
--
--
--
--
begin
select P#, PTitle into PID, PNAME from project where project.p# = projectid;
finalRow:= PID || ' ' || PNAME || ': ';
--
open query;
loop
fetch query into ENAME;
if query%NOTFOUND then exit;
end if;
finalRow:= finalRow || CASE WHEN SUBSTR(finalRow ,-2) <> ': '  THEN ', ' END || ENAME;
end loop;
close query;
dbms_output.put_line(finalRow);
return;
end PROJECTGROUPS;
/
execute PROJECTGROUPS(1001)
execute PROJECTGROUPS(1002)
execute PROJECTGROUPS(1003)
execute PROJECTGROUPS(1004)
execute PROJECTGROUPS(1005)
execute PROJECTGROUPS(1006)
show error

[电流输出]

SQL> execute PROJECTGROUPS(1001)
1001 Computation: Alvin, Peter

PL/SQL procedure successfully completed.

SQL> execute PROJECTGROUPS(1002)
1002 Study methods: Bob, Robert

PL/SQL procedure successfully completed.

SQL> execute PROJECTGROUPS(1003)
1003 Racing car: Robert

PL/SQL procedure successfully completed.

SQL> execute PROJECTGROUPS(1004)
1004 Football: Douglass, Eadger, Robert

PL/SQL procedure successfully completed.

SQL> execute PROJECTGROUPS(1005)
1005 Swimming: Robert

PL/SQL procedure successfully completed.

SQL> execute PROJECTGROUPS(1006)
1006 Training: Aban

如何循环我的代码，以便我可以使用执行 PROJECTGROUPS 调用它们。

Answer 1

您可以使用单个查询从每个项目中获取 20 名员工，如下所示，并在循环中使用它们来打印如下：

create or replace procedure PROJECTGROUPS(projectid IN WorksOn.P#%TYPE) -- you can remove input parameter as it is not used anywhere now
IS
BEGIN
FOR q in
(Select proj_detail, LISTAGG(name, ', ') WITHIN GROUP (ORDER BY NAME) AS NAMES from
(select project.p# || ' ' || project.ptitle as proj_detail,
       Employee.Name,
       Row_number() over (partition by project.p# order by employee.name) as rn
from project
Join WorksOn on project.p# = WorksOn.P#
join employee On Employee.E# = WorksOn.E#)
Where rn <= 20
GROUP BY PROJ_DETAIL)
LOOP
DBMS_OUTPUT.PUT_LINE(Q.PROJ_DETAIL || ': ' || Q.NAMES);
END LOOP;
END;
/