Reg-Logic for Query!

Question

Hi All,
In my application, there is an requirement for generating Autogen Sequence in two ways.
First Way: Using Autogen button.
For Ex: If the old symbol: ABCDEF00, the next Autogen sequence should be i.e, new symbol: ABCDEG00 .
Similarly if the symbol has old symbol:zzzzz00 new symbol should be AAAAA00.
As of now my logic is working perfectly accordingly to the above scenario.
Note: We will be changing only first 5 characters and last two digits I am appending as 00.
Second Way: Manually there can enter the symbol.
The problem I am facing in second method, since there can enter/ create a symbol using Alphanumeric.
For Ex: old Symbol: ABCD100, the next will be ABCD200 and soon till ABCD900.. Once the symbol ends with 9 then next sequence is replacing with some special characters as ABCD:00
Note: Symbol should not accept any special characters. If the symbol ABCD900 then next should be ABCD000. ‘9’ should be replaced with ‘0’ and soon. My logic will not work for alphanumeric.
Can anyone help me out my logic should accept both characters as well as numeric’s.
Following is the logic which currently i am using
DECLARE
v_symb_code VARCHAR2(7);
new_sym_code VARCHAR2(7);
v_count NUMBER;
v_auto_count NUMBER;
symb_code_new VARCHAR2(7);
BEGIN
SELECT COUNT(*) INTO v_auto_count FROM T_AUTOGEN_SYMBOL;
IF v_auto_count=0 THEN
SELECT symb_code INTO v_symb_code FROM t_symbol WHERE SYMB_MODIFIED_DATE=(SELECT MAX(SYMB_MODIFIED_DATE) FROM t_symbol) AND ROWNUM=1;
ELSE
SELECT ATGS_SYMB_CODE INTO v_symb_code FROM T_AUTOGEN_SYMBOL;
END IF;
LOOP
SELECT
-- 1st digit of new value
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),5,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),4,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),3,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),2,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),1,1),'Z','A',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),1,1),'A','B','B','C','C','D','D','E','E','F','F','G','G','H','H','I','I','J','J','K','K','L','L','M','M','N','N','O','O','P','P','Q','Q','R','R','S','S','T','T','U','U','V','V','W','W','X','X','Y','Y','Z',
CHR(ASCII(SUBSTR(SUBSTR (v_symb_code, 1, 5),1,1))+1))),
SUBSTR(SUBSTR (v_symb_code, 1, 5),1,1)),
SUBSTR(SUBSTR (v_symb_code, 1, 5),1,1)),
SUBSTR(SUBSTR (v_symb_code, 1, 5),1,1)),
SUBSTR(SUBSTR (v_symb_code, 1, 5),1,1))
||
-- 2nd digit of new value
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),5,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),4,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),3,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),2,1),'Z','A',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),2,1),'A','B','B','C','C','D','D','E','E','F','F','G','G','H','H','I','I','J','J','K','K','L','L','M','M','N','N','O','O','P','P','Q','Q','R','R','S','S','T','T','U','U','V','V','W','W','X','X','Y','Y','Z',
CHR(ASCII(SUBSTR(SUBSTR (v_symb_code, 1, 5),2,1))+1))),
SUBSTR(SUBSTR (v_symb_code, 1, 5),2,1)),
SUBSTR(SUBSTR (v_symb_code, 1, 5),2,1)),
SUBSTR(SUBSTR (v_symb_code, 1, 5),2,1))
||
-- 3rd digit of new value
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),5,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),4,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),3,1),'Z','A',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),3,1),'A','B','B','C','C','D','D','E','E','F','F','G','G','H','H','I','I','J','J','K','K','L','L','M','M','N','N','O','O','P','P','Q','Q','R','R','S','S','T','T','U','U','V','V','W','W','X','X','Y','Y','Z',
CHR(ASCII(SUBSTR(SUBSTR (v_symb_code, 1, 5),3,1))+1))),
SUBSTR(SUBSTR (v_symb_code, 1, 5),3,1)),
SUBSTR(SUBSTR (v_symb_code, 1, 5),3,1))
||
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),5,1),'Z',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),4,1),'Z','A',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),4,1),'A','B','B','C','C','D','D','E','E','F','F','G','G','H','H','I','I','J','J','K','K','L','L','M','M','N','N','O','O','P','P','Q','Q','R','R','S','S','T','T','U','U','V','V','W','W','X','X','Y','Y','Z',
CHR(ASCII(SUBSTR(SUBSTR (v_symb_code, 1, 5),4,1))+1))),
SUBSTR(SUBSTR (v_symb_code, 1, 5),4,1))
||
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),5,1),'Z','A',
DECODE(SUBSTR(SUBSTR (v_symb_code, 1, 5),5,1),'A','B','B','C','C','D','D','E','E','F','F','G','G','H','H','I','I','J','J','K','K','L','L','M','M','N','N','O','O','P','P','Q','Q','R','R','S','S','T','T','U','U','V','V','W','W','X','X','Y','Y','Z',
CHR(ASCII(SUBSTR(SUBSTR (v_symb_code, 1, 5),5,1))+1)))||'00' INTO new_sym_code
FROM dual;
symb_code_new := UPPER(new_sym_code);
SELECT COUNT(*) INTO v_count FROM t_symbol WHERE symb_code=symb_code_new AND ROWNUM<2;
/*IF v_count<1 THEN
SELECT COUNT(*) INTO v_count FROM t_symbol_wip WHERE symb_code=symb_code_new AND ROWNUM<2;
END IF;
DELETE FROM T_AUTOGEN_SYMBOL;
INSERT INTO T_AUTOGEN_SYMBOL(ATGS_SYMB_CODE,ATGS_MODIFIED_BY,ATGS_MODIFIED_DATE) VALUES(symb_code_new,v('APP_USER'),SYSDATE); */
EXIT WHEN v_count <1;
v_symb_code:=symb_code_new;
DBMS_OUTPUT.PUT_LINE(v_symb_code);
END LOOP;
:P39_SYMBOL := symb_code_new;
END;

Answer 1

I'd use a slightly different approach with the same end result: use and store numbers instead of this "Autogen sequence". When you use a number, you can easily add 1 or subtract 1. You probably only need that string for display. So use a function like below:
SQL> create function number2weirdstring (p_num in number) return varchar2
  2  as
  3    --
  4    -- The string looks like this AAAAA00.
  5    -- Define for each A what the acceptable characters can be
  6    -- For instance I'm defining them to accept [a-z] and [A-Z]
  7    -- And they are mapped to [0-25] and [26-51]. This leads to
  8    -- 52^5 possible combinations.
  9    --
10    l_character1 varchar2(1);
11    l_character2 varchar2(1);
12    l_character3 varchar2(1);
13    l_character4 varchar2(1);
14    l_character5 varchar2(1);
15  begin
16    l_character5 := chr( case when mod(p_num,52)                    < 26 then 97 else 39 end + mod(p_num,52) );
17    l_character4 := chr( case when mod(trunc(p_num/52),52)          < 26 then 97 else 39 end + mod(trunc(p_num/52),52) );
18    l_character3 := chr( case when mod(trunc(p_num/52/52),52)       < 26 then 97 else 39 end + mod(trunc(p_num/52/52),52) );
19    l_character2 := chr( case when mod(trunc(p_num/52/52/52),52)    < 26 then 97 else 39 end + mod(trunc(p_num/52/52/52),52) );
20    l_character1 := chr( case when mod(trunc(p_num/52/52/52/52),52) < 26 then 97 else 39 end + mod(trunc(p_num/52/52/52/52),52) );
21    return l_character1 || l_character2 || l_character3 || l_character4 || l_character5 || '00';
22  end number2weirdstring;
23  /
Functie is aangemaakt.And to show how the function works:
SQL> select number2weirdstring(0)
  2       , number2weirdstring(25)
  3       , number2weirdstring(26)
  4       , number2weirdstring(51)
  5       , number2weirdstring(52)
  6       , number2weirdstring(52*52-1)
  7       , number2weirdstring(52*52)
  8       , number2weirdstring(12893571)
  9    from dual
10  /
NUMBER2WEIRDSTRING(0)
NUMBER2WEIRDSTRING(25)
NUMBER2WEIRDSTRING(26)
NUMBER2WEIRDSTRING(51)
NUMBER2WEIRDSTRING(52)
NUMBER2WEIRDSTRING(52*52-1)
NUMBER2WEIRDSTRING(52*52)
NUMBER2WEIRDSTRING(12893571)
aaaaa00
aaaaz00
aaaaA00
aaaaZ00
aaaba00
aaaZZ00
aabaa00
bNKrp00
1 rij is geselecteerd.You only need to modify the function to accept the characters you want. But hopefully this example will get you started.
Regards,
Rob.