ORACLE 计算出数值表达式的值

-- 当出错的时候，就返回空值！



create or replace function cac_val(v_str varchar2)

return number

is

  v_res number(38,4);

begin

  execute immediate 'select '||v_str||' from dual' into v_res;

  return v_res;

exception when others then

  return null;

end;

/



select cac_val('2*10+3') from dual;

ceygle@SZTYORA> create or replace function cac_val(v_str varchar2)

  2  return number

  3  is

  4    v_res number(38,4);

  5  begin

  6    execute immediate 'select '||v_str||' from dual' into v_res;

  7    return v_res;

  8  exception when others then

  9    return 0;

 10  end;

 11  /



函数已创建。



eygle@SZTYORA> select cac_val('2*10+3') from dual;



CAC_VAL('2*10+3')

-----------------

               23