ist es möglich, in SQL-alphanumerischen Sequenz-Generator zu haben

Question

Ich brauche eine SQL-Abfrage zu schreiben, die folgende aphanumberic Sequenz in SQL

0001, 0002 zu drucken, ..., 0009, 000A, . .., 000Z, ..., 0010, 0011, ..., 001A, ... und so weiter, bis ..., ZZZZ

bitte beachten Sie: Alle Zeichen sind GROSS.

Vielen Dank im Voraus

Answer 1

Sie könnten eine Funktion wie folgt erstellen:

create function to_base_36 (n integer) return varchar2 
is 
    q integer; 
    r varchar2(100); 
begin 
    q := n; 
    while q >= 36 loop 
    r := chr(mod(q,36)+case when mod(q,36) < 10 then 48 else 55 end) || r; 
    q := floor(q/36); 
    end loop; 
    r := chr(mod(q,36)+case when mod(q,36) < 10 then 48 else 55 end) || r; 
    return lpad(r,4,'0'); 
end; 

und es dann wie folgt verwenden:

select rownum, to_base_36(rownum) 
from dual 
connect by level < 36*36*36*36; 

Oder, ohne eine Funktion zu erstellen:

with digits as 
(select n, chr(mod(n,36)+case when mod(n,36) < 10 then 48 else 55 end) d 
    from (Select rownum-1 as n from dual connect by level < 37) 
) 
select d1.n*36*36*36 + d2.n*36*36 + d3.n*36 + d4.n, d1.d||d2.d||d3.d||d4.d 
from digits d1, digits d2, digits d3, digits d4 

Answer 2

Sie könnten diese Funktion nutzen:

create or replace FUNCTION SEQGEN(vinp in varchar2, iSeq in INTEGER) 
RETURN VARCHAR2 is vResult VARCHAR2(32); 
    iBas INTEGER; iRem INTEGER; iQuo INTEGER; lLen CONSTANT INTEGER := 2; 
BEGIN 
    iBas := length(vInp); 
    iQuo := iSeq; 
    WHILE iQuo > 0 LOOP 
    iRem := iQuo mod iBas; 
    --dbms_output.put_line('Now we divide ' || lpad(iQuo,lLen,'0') || ' by ' || lpad(iBas,lLen,'0') || ', yielding a quotient of ' || lpad(TRUNC(iQuo/iBas) ,lLen,'0') || ' and a remainder of ' || lpad(iRem,lLen,'0') || ' giving the char: ' || substr(vInp, iRem, 1)); 
    iQuo := TRUNC(iQuo/iBas); 
    If iRem < 1 Then iRem := iBas; iQuo := iQuo - 1; End If; 
    vResult := substr(vInp, iRem, 1) || vResult; 
    END LOOP; 
    RETURN vResult; 
END SEQGEN; 

Versuchen Sie, die Funktion:

SELECT * FROM (
SELECT seqgen('ABCDEFGHIJKLMNOPQRSTUVWXYZ',rownum + 47989 --start value 
) Output, level evt FROM dual CONNECT BY level < 1679618) --stop value 
WHERE mod(evt,50000) = 0 OR output in ('0001','0002','0009','000A','000Z', 
             '0010','0011','001A','ZZZZ') 

Beachten Sie, wenn Sie die Zeichenfolge ändern, müssen Sie auch den Start ändern und den Wert zu stoppen.

Lesen Sie mehr über Zahlensysteme hier: Number System Conversion - Explanation

Answer 3

-- To get 00000 to ZZZZZ next auto alphanumeric sequence using this function [Please verify before use] 
-- This starts from 0-9 then A-Z and then increase next digit from 0-9 then A-Z 
-- You need to pass the starting/Last sequence as value to get next sequence 
CREATE OR REPLACE FUNCTION return_next_seq (curr_sequence VARCHAR2) 
RETURN VARCHAR2 IS 
retval VARCHAR2(4000) := NULL; 
retMaxval VARCHAR2(4000) := NULL; 
eval_digit CHAR(1) := NULL; 
original_sequence VARCHAR2(4000) := curr_sequence; 
curr1_sequence VARCHAR2(4000) := curr_sequence; 
BEGIN 
retval := original_sequence; 
FOR j IN REVERSE 1..LENGTH(curr1_sequence) LOOP -- Using reverse to know 
-- the exact digit position 
eval_digit := SUBSTR(curr1_sequence, LENGTH(curr1_sequence)); 
--IF (ASCII(eval_digit) BETWEEN 49 AND 56) OR 
--(ASCII(eval_digit) BETWEEN 97 AND 121) THEN 
IF (ASCII(eval_digit) BETWEEN 48 AND 56) OR 
(ASCII(eval_digit) BETWEEN 65 AND 89) THEN 
eval_digit := CHR(ASCII(eval_digit) +1); 
curr1_sequence := SUBSTR(curr1_sequence,1,LENGTH(curr1_sequence)-1); 
retval := curr1_sequence || eval_digit || SUBSTR(original_sequence, 
LENGTH(curr1_sequence || eval_digit)+1); 
EXIT; 
ELSE -- move to the next digit leaving the evaluated digit untouched. 
    IF (ASCII(eval_digit) = 57) THEN 
    eval_digit := CHR(ASCII(eval_digit) +8); 
    curr1_sequence := SUBSTR(curr1_sequence,1,LENGTH(curr1_sequence)-1); 
    retval := curr1_sequence || eval_digit || SUBSTR(original_sequence, 
    LENGTH(curr1_sequence || eval_digit)+1); 
    EXIT; 
    END IF; 
    IF (ASCII(eval_digit) = 90) THEN 
     retMaxval := eval_digit; 
     eval_digit := CHR(ASCII(eval_digit) -42);           
     curr1_sequence := SUBSTR(curr1_sequence,1,LENGTH(curr1_sequence)-1); 
     FOR k IN REVERSE 1..LENGTH(curr1_sequence) LOOP 
      IF (ASCII(SUBSTR(curr1_sequence,LENGTH(curr1_sequence))) BETWEEN 48 AND 56) OR (ASCII(SUBSTR(curr1_sequence,LENGTH(curr1_sequence))) BETWEEN 65 AND 89) THEN 
      retval := SUBSTR(curr1_sequence,0,LENGTH(curr1_sequence)-1) || CHR(ASCII(SUBSTR(curr1_sequence,LENGTH(curr1_sequence)))+1) || eval_digit || SUBSTR(retval, 
      LENGTH(curr1_sequence || eval_digit)+1); 
      ELSE 
       IF ASCII(SUBSTR(curr1_sequence,LENGTH(curr1_sequence))) = 57 THEN 
       retval := SUBSTR(curr1_sequence,0,LENGTH(curr1_sequence)-1) || CHR(65) || eval_digit || SUBSTR(retval, 
       LENGTH(curr1_sequence || eval_digit)+1); 
       ELSE 
        IF ASCII(SUBSTR(curr1_sequence,LENGTH(curr1_sequence))) = 90 AND LENGTH(curr1_sequence)>1 THEN 
        retval := SUBSTR(curr1_sequence,0,LENGTH(curr1_sequence)-1) || CHR(48) || eval_digit || SUBSTR(retval, 
        LENGTH(curr1_sequence || eval_digit)+1); 
        curr1_sequence := SUBSTR(curr1_sequence,1,LENGTH(curr1_sequence)-1); 
        retMaxval := retMaxval||'Z'; 
        ELSE 
        retMaxval := retMaxval||'Z'; 
        EXIT;     
        END IF; 
       END IF; 
      END IF; 
     END LOOP; 
      EXIT; 
    ELSE 
     curr1_sequence := SUBSTR(curr1_sequence,1,LENGTH(curr1_sequence)-1); 
    END IF; 
END IF; 
END LOOP; 
IF retval IS NULL OR (LENGTH(retval) = LENGTH(retMaxval)) THEN 
RETURN 'MAX'; 
END IF; 
RETURN retval; 
END; 

-- To verify, call this function like 
SELECT return_next_seq('ZY9Z') FROM dual; 
-- Any improvement suggestion is welcome! 
--- Thanks!..Sanjiv