Question

DECLARE
   TYPE EmpList IS TABLE OF varchar2(50) INDEX BY BINARY_INTEGER;

   temp    SYS_REFCURSOR;
   v_temp  varchar2(50);
   v_emp   EmpList;
BEGIN
   v_emp (1) := 'gaurav';
   v_emp (2) := 'manu';

   open temp for select v_emp(level) from dual connect by level<=2;
   loop
    fetch temp into v_temp;
     exit when temp%notfound;
       DBMS_OUTPUT.put_line (v_temp);
    end loop;
   close temp;

--the below part works, then why not the above part dint works
 for i in v_emp.first..v_emp.last
  loop
      dbms_output.put_line(v_emp(i));
  end loop;

EXCEPTION
   WHEN OTHERS
   THEN
      DBMS_OUTPUT.put_line (SQLERRM);
END;

任何人都可以告诉我为什么这个集合在这里工作？，它给了我no_data_found异常。

Answer 1

失败的原因是

v_emp(level)

在运行时被评估（作为它的变量），因此实际上将对所有行进行求值 v_emp(0);

如果您将阵列更改为

，则可以看到此信息

v_emp (0) := 'gaurav';
v_emp (1) := 'manu';

正确的方式（如果您不知道）是：

create TYPE EmpList IS TABLE OF varchar2(50);
/

然后：

v_emp := EmpList('gaurav', 'manu');
open temp for select column_value from table(v_emp);

Answer 2

试试这个：

DECLARE
   TYPE EmpList IS TABLE OF varchar2(50) INDEX BY BINARY_INTEGER;

   temp    SYS_REFCURSOR;
   v_temp  varchar2(50);
   v_emp   EmpList;
BEGIN
   v_emp (0) := 'gaurav';
   v_emp (1) := 'manu';

   open temp for select v_emp(level) from dual connect by level<=2;
   loop
    fetch temp into v_temp;
        exit when temp%notfound;
       DBMS_OUTPUT.put_line ('v_temp' || v_temp);
    end loop;
   close temp;

--the below part works, then why not the above part dint works
 for i in v_emp.first..v_emp.last
  loop
      dbms_output.put_line(v_emp(i));
  end loop;

EXCEPTION
   WHEN OTHERS
   THEN
      DBMS_OUTPUT.put_line (SQLERRM);
END;

使用集合时oracle pl / sql中的no_data_found异常

2 个答案: