oracle function ÖеĿÕÖµÅжÏÎÊÌâ

±ÈÈçÔÚijһoracle functionÖÐÓÐÈçÏ´úÂ룺
 
  dd varchar2(20);

  select aa  into dd  from table_A where bb= 'c'; // sql_a

  IF dd = ? THEN

    -- do something
  END IF;

  .....


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---

select aa  into dd  from table_A where bb= 'c';

Õâ¾ä»°ÕÒ²»µ½Êý¾Ý»á½øÒì³££¬Äã¿ÉÒÔÕâÑùȥд£º
begin
    select aa  into dd  from table_A where bb= 'c';
exception
    when no_data_found then
        dd := null;
end

if dd is null then
....

µ÷µ÷´úÂ룬¿ÉÄÜÓÐЩµØ·½Òª¸Ä

---

exception
            when no_data_found then
    do something;
    end ;


ûÓмǼµÄʱºòÓà no_data_found ²¶»ñ

---

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select aa  into dd  from table_A where bb= 'c';
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SQL> set serveroutput on
SQL>
SQL> declare
  2    v_test    char(1);
&nb