So here is the question:
Write code to take in an id and determine if the check digit is correct
UPDATED CODE:
Set SERVEROUTPUT ON
DECLARE
val_num NUMBER := '&user_input';
holder NUMBER := 0;
y NUMBER := 0;
conv_string VARCHAR2(20);
BEGIN
conv_string := to_char(val_num*10);
for x in 1..length(conv_string) loop
y := to_number(substr(conv_string, -x, 1));
if mod(x,2) = 0 then
y := y * 2;
if y > 9 then
y := y - 9;
end if;
end if;
holder := holder + y;
end loop;
dbms_output.put_line ('Check is '||(11-Mod(holder, 11)));
END luhn;
/
SET SERVEROUTPUT ON
The return is:
SQL> # loop
Enter value for user_input: 036532
old 2: val_num NUMBER := '&user_input';
new 2: val_num NUMBER := '036532';
Check is 2
It should be 6
Before actual execution
SET SERVEROUTPUT ON
to enable SQL*Plus to fetch database output buffer.
Here is solution: https://community.oracle.com/thread/837639?start=0&tstart=0
There are lots of different variations of the luhn algorithm, so looking at these implementations and your (I think incomplete) description in the comments I think this may be fairly close to what you are looking for, and gives the correct checksum for 036532 as per your initial question.
Hope it is helpfull
Set SERVEROUTPUT ON
DECLARE
val_num number := '036532';
holder NUMBER := 0;
y NUMBER := 0;
conv_string VARCHAR2(20);
BEGIN
conv_string := to_char(val_num);
FOR X IN 1..LENGTH(CONV_STRING) LOOP
Y := TO_NUMBER(SUBSTR(CONV_STRING, -X, 1));
IF ((X+1) > 10) THEN
Y := Y * 10;
ELSE
Y := Y * (X + 1);
END IF;
IF (Y >= 10) THEN
HOLDER := HOLDER + TO_NUMBER(substr(TO_CHAR(Y), 1, 1)) + TO_NUMBER(substr(TO_CHAR(Y), 2, 1));
ELSE
HOLDER := HOLDER + Y;
END IF;
END LOOP;
HOLDER := MOD(HOLDER, 11);
Holder := 11 - mod(holder, 11);
dbms_output.put_line ('Check is '|| holder);
END luhn;
/
SET SERVEROUTPUT ON
Related
I have a sample number in a column of oracle table which is binary's 2's complimanet -
e.g 0110001000110111
I want to convert this to normal decimal number in 2's compliment.
Expected output-
Reference link - https://www.rapidtables.com/convert/number/decimal-to-binary.html
You can loop as applying powers of 2 while multiplying by each bit(0 or 1) starting from the right end of your presented value such as
SET SERVEROUTPUT ON
DECLARE
bin_nr VARCHAR2(100) := '0110001000110';
dec_nr NUMBER;
BEGIN
FOR i IN 1..LENGTH(bin_nr)
LOOP
dec_nr := NVL(dec_nr,0) + SUBSTR(bin_nr,-i,1)*(2**(i-1));
END LOOP;
DBMS_OUTPUT.PUT_LINE(dec_nr);
END;
/
which results 3142 as the decimal value.
Demo
For 2s compliment, the most-significant bit represents the sign bit and if that is 1 then you have a negative number:
DECLARE
bin_nr VARCHAR2(100) := '1111001110111010';
sign PLS_INTEGER;
dec_nr PLS_INTEGER;
BEGIN
IF SUBSTR(bin_nr, 1, 1) = '1' THEN
bin_nr := TRANSLATE(bin_nr, '01', '10');
sign := -1;
dec_nr := 1;
ELSE
sign := 1;
dec_nr := 0;
END IF;
FOR i IN 1 .. LENGTH(bin_nr) LOOP
IF SUBSTR(bin_nr, -i, 1) = '1' THEN
dec_nr := dec_nr + POWER(2, i-1);
END IF;
END LOOP;
dec_nr := dec_nr * sign;
DBMS_OUTPUT.PUT_LINE(dec_nr);
END;
/
Outputs -3142
If you are expecting an N-bit binary number as the input (for example, the link in the question expects a 16-bit binary number as an input for 2s compliment) then you should LPAD with zeroes if you have fewer than that many bits.
db<>fiddle here
Wanted to create a function that can return records containing the number data type which are prime number
But getting warning of compilation error. What is the mistake in the code.I am a beginner in pl/sql.
CREATE OR REPLACE FUNCTION isPrime (num number)
RETURN number
IS
retVal number;
BEGIN
DECLARE
prime_or_notPrime number;
counter number;
retVal:= 1;
prime_or_notPrime:= 1
counter:= 2
WHILE (counter <= num/2) LOOP
IF (mod(num ,counter)= 0) THEN
prime_or_notPrime: = 0
EXIT;
END IF;
IF (prime_or_notPrime = 1 ) THEN
retVal: = 1;
counter: = counter + 1
END IF;
END LOOP;
return retVal;
END;
/
What is the mistake in the code
The DECLARE is invalid syntax for a function/procedure. You want to declare the variables between the IS and BEGIN keywords.
Then you are missing a ; statement terminator after prime_or_notPrime:= 1 and counter:= 2.
Then you have:
prime_or_notPrime: = 0 instead of prime_or_notPrime := 0;
retVal: = 1; instead of retVal := 1; and
counter: = counter + 1 instead of counter := counter + 1; (they all have a space between : and = and some are missing ; again).
You never set retVal to anything other than 1.
You do not handle NULL values or values lower than 2.
Fixing that (and the indentation) gives:
CREATE OR REPLACE FUNCTION isPrime (num number)
RETURN number
IS
retVal number;
prime_or_notPrime number;
counter number;
BEGIN
IF NUM IS NULL OR NUM < 2 THEN
RETURN 0;
END IF;
retVal:= 1;
prime_or_notPrime:= 1;
counter:= 2;
WHILE (counter <= num/2) LOOP
IF (mod(num ,counter)= 0) THEN
prime_or_notPrime := 0;
retVal := 0;
EXIT;
END IF;
IF (prime_or_notPrime = 1 ) THEN
counter := counter + 1;
END IF;
END LOOP;
return retVal;
END;
/
Note: the prime_or_notprime variable is not controlling anything as, as soon as you set it to 0 you EXIT from the loop so it will never be used again. Having noted that, you can get rid of the final IF statement and just always increment the counter.
You can simplify it to:
CREATE OR REPLACE FUNCTION isPrime (
num number
) RETURN number DETERMINISTIC
IS
BEGIN
IF NUM IS NULL OR NUM < 2 THEN
RETURN 0;
END IF;
FOR counter IN 2 .. SQRT(num) LOOP
IF MOD(num, counter) = 0 THEN
RETURN 0;
END IF;
END LOOP;
RETURN 1;
END;
/
You can then consider improvements. Such as starting by checking 2 as a special case and then skipping all the other even numbers.
db<>fiddle here
I want to create a plsql procedure to calculate the factorial of a given number.
This is the procedure:
CREATE OR REPLACE PROCEDURE fact(x IN number, fact OUT number)
IS
BEGIN
while x > 0 loop
fact := x*fact;
x := x-1;
END loop;
END;
/
Warning: Procedure created with compilation errors.
and this is where I'm calling the function
DECLARE
x number := &x;
fact number := 1;
BEGIN
fact(x,fact);
dbms_output.put_line('Factorial is: '||fact);
END;
and this is the error I'm getting:
Enter value for x: 5
old 2: x number := &x;
new 2: x number := 5;
fact(x,fact);
*
ERROR at line 5:
ORA-06550: line 5, column 1:
PLS-00221: 'FACT' is not a procedure or is undefined
ORA-06550: line 5, column 1:
PL/SQL: Statement ignored
You need to convert your creation of procedure like this :
SQL> CREATE OR REPLACE PROCEDURE fact(x IN OUT number, fact OUT number) IS
BEGIN
while x > 0 loop
fact := x * nvl(fact, 1);
x := x - 1;
END loop;
END;
/
and call :
SQL> SET SERVEROUTPUT ON;
SQL> DECLARE
x number := &x;
v_fact number := 1;
BEGIN
fact(x, v_fact);
dbms_output.put_line('Factorial is: ' || v_fact);
END;
Factorial is: 120
You can not use a variable of type IN as an assignment target
You need to initialize a null variable fact as nvl(fact,1) or fact := 1; just before the while x > 0
Actually, you even do not need an extra parameter fact OUT number for procedure named fact, and make that as local. So, your procedure may be replaced with this :
SQL> CREATE OR REPLACE PROCEDURE fact(x IN OUT number) IS
fact number := 1;
BEGIN
while x > 0 loop
fact := x * fact;
x := x - 1;
end loop;
x := fact;
END;
/
Therefore, should be invoked as :
SQL> DECLARE
x number := &x;
BEGIN
fact(x);
dbms_output.put_line('Factorial is: ' || x);
END;
Factorial is: 120
You might consider rewriting this as a function along the lines of the following:
CREATE OR REPLACE FUNCTION fact(pinX IN INT)
RETURN INT
IS
nResult INT := 1;
BEGIN
FOR i IN 2..pinX LOOP
nResult := i * nResult;
END LOOP;
RETURN nResult;
END FACT;
dbfiddle here
Best of luck.
Input String : “a4b4c2d9d9c2e6e6b4s2o1o1s2a4w2r8r8k3g5g5k3w2”
I tried this code as first step:
declare
word varchar2(50) := 'a4b4c2d9d9c2e6e6b4s2o1o1s2a4w2r8r8k2g5g5k2w2';
num number := length(word)/2;
name_array dbms_sql.varchar2_table;
begin
dbms_output.put_line(word);
FOR i IN 1..num LOOP
name_array(i) := substr(word, -2*i, 2);
END LOOP;
FOR i IN name_array.FIRST .. name_array.LAST LOOP
dbms_output.put_line(name_array(i));
END LOOP;
end;
This code creates only an array of string. Not xml format. I need this output:
Which SQL functions,conditional clauses... do I need to use?
Oracle Setup:
CREATE OR REPLACE TYPE CHARS_TABLE IS TABLE OF CHAR(2);
/
CREATE OR REPLACE TYPE INTEGERS_TABLE IS TABLE OF INTEGER;
/
PL/SQL:
This assumes a well-formed set of character pairs and just indents each pair to the appropriate level:
DECLARE
word VARCHAR2(50) := 'a4b4c2d9d9c2e6e6b4s2o1o1s2a4w2r8r8k2g5g5k2w2';
num PLS_INTEGER := LENGTH( word ) / 2;
name_array CHARS_TABLE := CHARS_TABLE();
depth_array INTEGERS_TABLE := INTEGERS_TABLE();
open_array INTEGERS_TABLE := INTEGERS_TABLE();
BEGIN
name_array.EXTEND( num );
depth_array.EXTEND( num );
open_array.EXTEND( num );
name_array(1) := SUBSTR( word, 1, 2 );
depth_array(1) := 1;
open_array(1) := 1;
FOR i IN 2 .. num LOOP
name_array(i) := SUBSTR( word, 2*i - 1, 2 );
open_array(i) := 1;
FOR j IN 1 .. i-1 LOOP
IF name_array(j) = name_array(i) THEN
open_array(i) := -open_array(i);
END IF;
END LOOP;
depth_array(i) := depth_array(i-1) + open_array(i);
END LOOP;
FOR i IN 1 .. num LOOP
FOR j IN 2 .. depth_array(i) + CASE open_array(i) WHEN 1 THEN 0 ELSE 1 END LOOP
DBMS_OUTPUT.PUT( ' ' );
END LOOP;
DBMS_OUTPUT.PUT_LINE( name_array(i) );
END LOOP;
END;
/
Output:
a4
b4
c2
d9
d9
c2
e6
e6
b4
s2
o1
o1
s2
a4
w2
r8
r8
k2
g5
g5
k2
w2
Update - Simpler Stack-Based Version:
DECLARE
word CONSTANT VARCHAR2(50) := 'a4b4c2d9d9c2e6e6b4s2o1o1s2a4w2r8r8k2g5g5k2w2';
num CONSTANT PLS_INTEGER := LENGTH( word ) / 2;
name_array CHARS_TABLE := CHARS_TABLE();
depth PLS_INTEGER := 0;
name CHAR(2);
PROCEDURE indent( depth PLS_INTEGER, name CHAR )
IS
BEGIN
FOR j IN 2 .. depth LOOP
DBMS_OUTPUT.PUT( ' ' );
END LOOP;
DBMS_OUTPUT.PUT_LINE( name );
END;
BEGIN
name_array.EXTEND( num );
FOR i IN 1 .. num LOOP
name := SUBSTR( word, 2*i - 1, 2 );
IF depth > 0 AND name = name_array(depth) THEN
indent(depth,name);
depth := depth - 1;
ELSE
depth := depth - 1;
name_array(depth) := name;
indent(depth,name);
END IF;
END LOOP;
END;
/
DECLARE
vs_CurrentChar VARCHAR2(1);
vs_NextChar VARCHAR2(1);
vs_TempText VARCHAR2(100);
vs_InputText VARCHAR2(100) := 'abcdffdcba';
vn_LengthOfText NUMBER := 1;
vn_WhileIndex NUMBER := 1;
vs_Spaces VARCHAR(100);
BEGIN
vs_TempText := NULL;
vs_CurrentChar := substr(vs_InputText, vn_WhileIndex, vn_LengthOfText);
dbms_output.put_line(vs_CurrentChar);
WHILE vn_WhileIndex < length(vs_InputText) - 1 LOOP
vs_NextChar := substr(vs_InputText, vn_WhileIndex + 1, vn_LengthOfText);
EXIT WHEN vs_CurrentChar = vs_NextChar;
vs_TempText := vs_TempText || vs_CurrentChar;
vs_CurrentChar := vs_NextChar;
vs_Spaces := NULL;
FOR i IN 1 .. vn_WhileIndex LOOP
vs_Spaces := vs_Spaces || chr(9); --'*';
END LOOP;
dbms_output.put_line(vs_Spaces || vs_CurrentChar);
vn_WhileIndex := vn_WhileIndex + 1;
END LOOP;
dbms_output.put_line(vs_Spaces || vs_CurrentChar);
FOR i IN 1 .. length(vs_TempText) LOOP
vs_Spaces := substr(vs_Spaces, vn_LengthOfText, length(vs_Spaces) - 1);
vs_CurrentChar := substr(vs_TempText, -i, vn_LengthOfText);
dbms_output.put_line(vs_Spaces || vs_CurrentChar);
END LOOP;
END;
/
And output:
a
b
c
d
f
f
d
c
b
a
even, if you put '*'; instead of chr(9); then output will look like as:
a
*b
**c
***d
****f
****f
***d
**c
*b
a
Imagine - there's a house with 80 flats. It has 4 floors and 5 blocks. Each block has 4 flats.
User is asked to input flat number and Pascal program is supposed to calculate and output flat number. This must be calculated using some kind of formula. The only tip I have is that I have to use div and mod operations.
This is how the house looks like -
So far, I've created program, that loops through all 80 flats and after each 16 flats increases block value and after each 4 blocks increases stair.
This is my code:
program project1;
var
i, floors, blocks, flats, flat, block, floor, blockCounter, floorCounter : integer;
begin
floors := 4;
blocks := 5;
flats := 80;
while true do
begin
write('Flat number: ');
read(flat);
block := 1;
floor := 1;
blockCounter := 0;
floorCounter := 0;
for i := 1 to 80 do
begin
blockCounter := blockCounter + 1;
floorCounter := floorCounter + 1;
if (floorCounter = 4) then
begin
floorCounter := 0;
floor := floor + 1;
end;
if (blockCounter > 16) then
begin
block := block + 1;
blockCounter := 0;
floorCounter := 0;
floor := 1;
end;
if (i = flat) then
begin
writeln('Flat nr. ', flat, ' is in ', floor, '. floor and in ', block, '. block!');
end;
end;
end;
end.
Is there anyone who can help me with this?
I've finally solved my problem myself.
I finally undersood how div works, so I was able to solve this.
program Maja;
var dzivoklis, kapnutelpa, stavs : integer;
begin
while true do
begin
write('Ievadi dzivokla numuru: ');
read(dzivoklis);
kapnutelpa := ((dzivoklis - 1) div 16) + 1;
stavs := (((dzivoklis - 1) mod 16) div 4) + 1;
writeln('Kapnutelpa: ', kapnutelpa);
writeln('Stavs: ', stavs);
writeln();
end;
end.