可以在Oracle-Sql中使用Function作为DML吗？

Question

所以我接到一个任务，执行以下任务。

   Create a simple program to demonstrate the use of stored functions for
       a) Retrieving formatted information by giving the employee id.
       b) Performing DML commands (Insert, Update and Delete)
       c) Checking palindrome String

使用了以下表格

SQL> desc Employee01;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 EMPNO                                     NOT NULL NUMBER(38)
 ENAME                                     NOT NULL VARCHAR2(20)
 DEPTNO                                    NOT NULL VARCHAR2(5)
 JOB                                                VARCHAR2(20)
 HIREDDATE                                          DATE
 SALARY                                             NUMBER(38)

前面两个我都做过，但是手写体那个我不知道怎么下手。希望得到帮助。

编辑：在DMLPalindrome代码中得到了帮助。

CREATE OR REPLACE FUNCTION FPal(
  str VARCHAR2)
     RETURN VARCHAR2
  IS
     l VARCHAR2;
     t VARCHAR2;
     res  VARCHAR2 (130);
  BEGIN
     FOR i IN REVERSE 1..Length(s) LOOP  
        l := Substr(str, i, 1);
        t := t  
             ||'' 
             ||l;  
    END LOOP;  

    IF t = str THEN 
      dbms_output.Put_line(t  
                           ||'' 
                           ||' is palindrome');  
    ELSE 
      dbms_output.Put_line(t  
                           ||'' 
                           ||' is not palindrome');  
    END IF;  
     RETURN (res);
  END FPal;
 /

Answer 1

下面是一个可能的固定函数。

    SQL> set serveroutput on
    SQL> CREATE OR REPLACE FUNCTION FPal(
      2    str VARCHAR2)
      3       RETURN  VARCHAR2
      4    IS
      5       l CHAR;
      6       t VARCHAR2(128);
      7    BEGIN
      8       FOR i IN REVERSE 1..Length(str) LOOP
      9          l := Substr(str, i, 1);
     10          t := t  || l;
     11      END LOOP;
     12  
     13      IF t = str THEN
     14        dbms_output.Put_line(t  ||' is palindrome');
     15        return 'TRUE';
     16      ELSE
     17        dbms_output.Put_line(t  ||' is not palindrome');
     18        return 'FALSE';
     19      END IF;
     20    END FPal;
     21   /

    Function created.

    SQL> show errors
    No errors.

测试。

    SQL> select fpal('ABBA') from dual;

    FPAL('ABBA')
    --------------------------------------------------------------------------------
    TRUE

    ABBA is palindrome
    SQL> select fpal('BABA') from dual;

    FPAL('BABA')
    --------------------------------------------------------------------------------
    FALSE

    ABAB is not palindrome
SQL> 

Answer 2

一种不同的方法：将输入字符串分割成行和 融合 他们回，倒。比较这两个值，然后决定。

SQL> create or replace function f_pal (par_val in varchar2) return varchar2 is
  2    l_val varchar2(200) := replace(par_val, ' ', '');
  3    l_rev varchar2(200);
  4  begin
  5    select listagg(regexp_substr(l_val, '[^.]', 1, level), '')
  6           within group (order by level desc)
  7      into l_rev
  8      from dual
  9      connect by level <= length(l_val);
 10
 11    return 'palindrome: ' || case when l_rev = l_val then 'YES'
 12                                  else 'NO'
 13                             end;
 14  end;
 15  /

Function created.

检验。

SQL> with
  2  test (col) as
  3    (select 'little' from dual union all
  4     select 'radar'  from dual union all
  5     select '12321'  from dual union all
  6     select 'ana voli milovana' from dual
  7    )
  8  select col, f_pal(col) result
  9  from test;

COL               RESULT
----------------- ------------------------------
little            palindrome: NO
radar             palindrome: YES
12321             palindrome: YES
ana voli milovana palindrome: YES

SQL>