SQL REPLACE special characters with value from another table - sql

Question

All,
I am trying to replace the special characters in a string with the URL
encoding values to which they correspond. Below is some example code I have
been working with.
Thanks for the help.
create table #url_encoding_lookup(character varchar(10), code varchar (20))
insert into #url_encoding_lookup (character, code)
values
('!', '%21'),
('"', '%22'),
('#', '%23'),
('$', '%24'),
('%', '%25'),
('&', '%26'),
('''', '%27'),
('(', '%28'),
(')', '%29'),
('*', '%2A'),
('+', '%2B'),
(',', '%2C'),
('-', '%2D'),
('.', '%2E'),
('/', '%2F')
Create table #data
(string varchar (200))
insert into #data
values
('Jim (BoB)'),
('Will''s Place'),
('Auto-Mart')
select * from #data
select * from #url_encoding_lookup
desired results would be
Jim %28Bob%29
Will%27s Place
Auto%2DMart

Answer 1

Create procedure
BEGIN
DECLARE _end BOOLEAN DEFAULT FALSE;
DECLARE _result CHAR(200) DEFAULT str;
DECLARE _find VARCHAR(32);
DECLARE _replace VARCHAR(32);
DECLARE _cur CURSOR FOR SELECT _character, _code FROM url_encoding_lookup;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET _end = TRUE;
OPEN _cur;
_loop: LOOP
FETCH _cur INTO _find, _replace;
IF _end THEN
LEAVE _loop;
END IF;
SET _result = REPLACE(_result, _find, _replace);
END LOOP _loop;
CLOSE _cur;
RETURN _result;
END
Then
SELECT _replace_chars(name) FROM `data`
Result
Jim %28BoB%29
Will%27s Place
Auto%2DMart

Answer 2

ALTER FUNCTION [dbo].[udf_ReplaceYouCoded]
(
#the_string nvarchar(max)
)
RETURNS NVARCHAR(MAX)
AS
BEGIN
declare #temp_field nvarchar(max)
create table #url_encoding_lookup(character varchar(10), code varchar (20))
insert into #url_encoding_lookup (character, code)
values
('!', '%21'),
('"', '%22'),
('#', '%23'),
('$', '%24'),
('%', '%25'),
('&', '%26'),
('''', '%27'),
('(', '%28'),
(')', '%29'),
('*', '%2A'),
('+', '%2B'),
(',', '%2C'),
('-', '%2D'),
('.', '%2E'),
('/', '%2F')
declare #x as int
set #x = 1
--LOOP #the_string
while #i < len(#the_string)
if(substring(#the_string,x,1) = (select character from #url_encoding_lookup where character = substring(#the_string,x,1)))
begin
#temp_field = #temp_field + (select code from #url_encoding_lookup where character = substring(#the_string,x,1))
end
else
begin
#temp_field = #temp_field + substring(#the_string,x,1)
end
select #x = #x + 1
end
RETURN #temp_field
END

Answer 3

ALTER function [dbo].[udf_ReplaceSpecialChars]
(#s varchar(256))
returns varchar(256)
as
begin
-- declare #s varchar(256) set #s = 'Jim (P)' --test
if #s is null
return null
declare #s2 varchar(256)
set #s2 = '' --set variable to empty string. ready to recieve values
declare #l int
set #l = len(#s) --determin the number of characters in #s
declare #p int
set #p = 1 --set beginning string position
while #p <= #l begin
declare #c int
set #c = ascii(substring(#s, #p, 1)) --find the ascii number for 1st
character
declare #nc varchar(256)
set #nc = (select code from url_encoding_lookup where ascii_code = #c) --
get corresponding URL encoding string from lookup table
if #c between 33 and 47 or #c between 58 and 64 or #c between 91 and 96
or #c between 123 and 255 --when looping through each character, if special
character
set #s2 = #s2 + #nc --then use string from lookup table
else if #c = 32 or #c between 48 and 57 or #c between 65 and 90 or #c
between 97 and 122 --if character is not special
set #s2 = #s2 + char(#c) --then find char value of character
set #p = #p + 1 --set position to next charachter for loop to look at
end
if len(#s2) = 0
return null
return #s2 --return rebuilt string
end

Answer 4

You can replace the special characters using the following regular expression [\u0100-\uffff]
select regexp_replace(column, '[\u0100-\uffff]', '')