Char shifting for given string - sql-server

Question

Suppose we have a varchar value like 'Durgesh' and I want to increase (Char +2) of every characters which are given in 'Durgesh'. Example:
D --> F
U --> W
R --> T
G --> I
E --> G
S --> U
H --> J
So if we put the parameter 'Durgesh', then we need the output 'Fwtiguj'.
How can I implement this with a SQL query?

Answer 1

This would be your function:
CREATE FUNCTION [dbo].[shifting](#Input varchar(100))
RETURNS varchar(100)
AS
BEGIN
declare
#i INT=0,
#a varchar(100) =''
while #i<LEN(#Input)
BEGIN
SET #i = #i +1
set #a = #a + char(ascii(substring(#Input,#i,1))+2)
end
RETURN #a
END
You call it as:
select [dbo].[shifting]('Durgesh') as [a]
Here is a demo
Here is a new function that will resolve the YZ and yz problem:
CREATE FUNCTION [dbo].[shifting](#Input varchar(100))
RETURNS varchar(100)
AS
BEGIN
declare
#i INT=0,
#a varchar(100) =''
while #i<LEN(#Input)
BEGIN
SET #i = #i +1
if substring(#Input,#i,1) in ('y','Y')
if ascii(substring(#Input,#i,1)) = ascii('y')
set #a = #a + 'a'
else
set #a = #a + 'A'
else
if substring(#Input,#i,1) in ('z','Z')
if ascii(substring(#Input,#i,1)) = ascii('z')
set #a = #a + 'b'
else
set #a = #a + 'B'
else
set #a = #a + char(ascii(substring(#Input,#i,1))+2)
end
RETURN #a
END
Here is a demo

Answer 2

Use below code :-
declare #val varchar(10) = 'Durgesh'
DECLARE #i INT = 0
WHILE #i < LEN(#val)
BEGIN
PRINT( CHAR( ASCII(SUBSTRING(#val,#i,1)) +2 ) )
SET #i = #i + 1
End

Answer 3

You can do this pretty easily with a tally table. I keep one on my database a view. Here is the code for my tally table. The biggest advantage a tally table has here is we don't have to do any looping!!!
create View [dbo].[cteTally] as
WITH
E1(N) AS (select 1 from (values (1),(1),(1),(1),(1),(1),(1),(1),(1),(1))dt(n)),
E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
cteTally(N) AS
(
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
)
select N from cteTally
Now that we have a tally table we can use it to make your character shift. This will work on nearly any string (until you hit the top end of the ASCII values).
declare #Val varchar(10) = 'Durgesh'
select stuff((
select char(ASCII(substring(#Val, t.N, 1)) + 2)
from cteTally t
where t.N <= len(#Val)
order by t.N
FOR XML PATH('')), 1, 0, '')
--EDIT--
Here is a new version that will "wrap" the characters back to the beginning.
declare #Val varchar(100) = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
select stuff((
select case when (ASCII(substring(#Val, t.N, 1)) > 88 AND ASCII(substring(#Val, t.N, 1)) < 91) --Upper case
OR ASCII(substring(#Val, t.N, 1)) > 120 --lower case
then char(ASCII(substring(#Val, t.N, 1)) - 24) else char(ASCII(substring(#Val, t.N, 1)) + 2) end
from cteTally t
where t.N <= len(#Val)
order by t.N
FOR XML PATH('')), 1, 0, '')