我认为，如果我正确理解了这个问题，您希望将过程的输入参数评估为单个值或它们的集合。您不能将由 select 语句检索到的表中的单个值与值集合进行比较。那永远都行不通。
在这种情况下，你可以试试这样的方法
测试用例
SQL> create table emp ( emp_id number , name varchar2(100) , manager varchar2(100) , emp_status varchar2(1) ) ;
Table created.
SQL> insert into emp values ( 1 , 'John' , 'Bill' , 'A' ) ;
SQL> insert into emp values ( 2 , 'Mike' , 'Bill' , 'A' ) ;
SQL> insert into emp values ( 3 , 'Sara' , 'Bill' , 'A' ) ;
SQL> insert into emp values ( 4 , 'Dany' , 'Bill' , 'A' ) ;
SQL> insert into emp values ( 5 , 'Mila' , 'Anne' , 'B' ) ;
SQL> insert into emp values ( 6 , 'Jean' , 'Anne' , 'B' ) ;
1 row created.
1 row created.
1 row created.
1 row created.
1 row created.
1 row created.
SQL> commit ;
Commit complete.
SQL> create table dept ( dtpt_num number , cross_dept varchar2(3) ) ;
Table created.
SQL> insert into dept values ( 100 , 'DEV' ) ;
1 row created.
SQL> insert into dept values ( 200 , 'HRM' ) ;
1 row created.
SQL> col name for a20
SQL> col manager for a20
SQL> select * from emp ;
EMP_ID NAME MANAGER E
---------- -------------------- -------------------- -
1 John Bill A
2 Mike Bill A
3 Sara Bill A
4 Dany Bill A
5 Mila Anne B
6 Jean Anne B
6 rows selected.
SQL> select * from dept ;
DTPT_NUM CRO
---------- ---
100 DEV
200 HRM
现在，让我们构建一个演示函数，根据 id 获取随机工资
SQL> create or replace function get_salary ( pempid in number )
return number deterministic
is
out_sal number;
begin
select round(dbms_random.value(1000,3000),0) into out_sal from dual ;
return out_sal ;
end;
/
Function created.
让我们在 emp 表中添加一个新列，以便按部门连接两个表
SQL> alter table emp add dept_id number ;
Table altered.
SQL> update emp set dept_id = ( case when EMP_STATUS = 'A' then 100 else 200 end ) ;
6 rows updated.
SQL> commit ;
Commit complete.
SQL> select * from emp
2 ;
EMP_ID NAME MANAGER E DEPT_ID
---------- -------------------- -------------------- - ----------
1 John Bill A 100
2 Mike Bill A 100
3 Sara Bill A 100
4 Dany Bill A 100
5 Mila Anne B 200
6 Jean Anne B 200
6 rows selected.
我们现在可以连接两个表并使用演示函数来获得随机工资
SQL> select e.emp_id , e.name, e.manager, d.cross_dept, d.dtpt_num , get_salary(e.emp_id) as salary
from emp e
join Dept d on e.DEPT_ID = d.dtpt_num ;
EMP_ID NAME MANAGER CRO DTPT_NUM SALARY
---------- -------------------- -------------------- --- ---------- ----------
1 John Bill DEV 100 2129
2 Mike Bill DEV 100 1215
3 Sara Bill DEV 100 2930
4 Dany Bill DEV 100 1347
5 Mila Anne HRM 200 1664
6 Jean Anne HRM 200 1770
6 rows selected.
现在，让我们构建一个过程，该过程将考虑输入参数可能是单个员工或用逗号分隔的列表并将结果存储在临时表中（仅出于演示目的，您可以使用sys_refcursor 对象）
SQL> create table tmp_results as
select e.emp_id , e.name, e.manager, d.cross_dept, d.dtpt_num , get_salary(e.emp_id) as salary
from emp e
join Dept d on e.DEPT_ID = d.dtpt_num
where 1 = 2 ;
Table created.
create or replace procedure emp_test ( pemployee in varchar2 )
is
v_counter_records pls_integer;
v_num_of_values pls_integer;
curr_val varchar2(10);
begin
v_counter_records := regexp_count ( pemployee , ',' , 1 , 'i' );
if v_counter_records = 0
then
insert into tmp_results
select e.emp_id , e.name, e.manager, d.cross_dept, d.dtpt_num , get_salary(e.emp_id) as salary
from emp e
join Dept d on e.DEPT_ID = d.dtpt_num
where e.emp_id = to_number(pemployee) ;
else
v_num_of_values := v_counter_records + 1;
for rec in 1 .. v_num_of_values
loop
curr_val := regexp_substr( pemployee, '[^,]+', 1 , rec );
insert into tmp_results
select e.emp_id , e.name, e.manager, d.cross_dept, d.dtpt_num , get_salary(e.emp_id) as salary
from emp e
join Dept d on e.DEPT_ID = d.dtpt_num
where e.emp_id = to_number(curr_val);
end loop;
end if;
end;
/
Procedure created.
SQL> exec emp_test( '1,2,3' );
PL/SQL procedure successfully completed.
SQL> select * from tmp_results ;
EMP_ID NAME MANAGER CRO DTPT_NUM SALARY
---------- -------------------- -------------------- --- ---------- ----------
1 John Bill DEV 100 2386
2 Mike Bill DEV 100 1531
3 Sara Bill DEV 100 2202
注意事项
- 我的示例只是向您展示如何拆分在过程输入中用作单个参数的参数列表。
- 您还可以将查询更改为使用
IN 而不是= 在存在多个值时评估条件。
- 我没有为该函数添加任何特殊逻辑，因为在示例中不需要它。
- 您也可以使用
WITH 声明来获取稍后要比较的员工列表，但您的问题并不清楚您何时使用该 CTE 结构。