Step 1: Write Script for function
CREATE FUNCTION [dbo].[RemoveSpecialChars] (@string VARCHAR(1000))
RETURNS varchar(1000)
AS
BEGIN
DECLARE @validValues varchar(200)='@/,.[](/) ''{}' -- enter characters which you wants
DECLARE @validTable table(validkeywords varchar(200))
DECLARE @ids INT=1
WHILE @ids<=DATALENGTH(@validValues)
BEGIN
INSERT INTO @validTable VALUES(LTRIM(RTRIM(ASCII(SUBSTRING(@validValues,@ids,1)))))
SET @ids=@ids+1
END
DECLARE @short varchar(100)
DECLARE @index INT =1
DECLARE @str varchar(1000)=''
WHILE @index <= DATALENGTH(@string)
BEGIN
SET @short=ASCII(SUBSTRING(LOWER(@string), @index, 1))
IF (@short BETWEEN 97 AND 122) OR (@short BETWEEN 48 AND 57) OR (@short IN (SELECT DISTINCT * FROM @validTable))
BEGIN
SET @str=@str+SUBSTRING(@string, @index, 1)
END
SET @index =@index+1
END
RETURN @str
END
Step 2: Execute function to create it (press F5 to execute)
Step 3: After create the function, pass string as a parameter to get result
select dbo.RemoveSpecialChars('sds{///}\||+-()*. dsdsSWE.s@3223')
Output will be: sds{///}(). dsdsSWE.s@3223
