Remove special characters in SQL

Question

      I have to remove the special characters from the selected string.

for example : I have string 'a&b' or 'a & b'. How can i remove special characters and concatenate these string into 'ab'.

Please can any one tell me.

SELECT @id= (UPPER(SUBSTRING(@a,1,2)))+(UPPER(SUBSTRING((SELECT table.column2 FROM tablename WHERE tablename.column1 = @b),1,2))) + RIGHT('000000000' + CAST(@count as varchar(10)), 6) 

Solution 1

The function is by far the best option, if you must do it inline you can replace within a recursive CTE and use that as the base table;

select 1 as id,
       'qw2££!"£$%^&**(' as F into #TESTTABLE
insert #TESTTABLE 
values (2, 'xxx'),
       (3, ''), 
       (4,'$'),
       (5,'qq""ee$$')

;with cte(id, stripped) as (
    select id, cast(F as varchar(1024)) from #TESTTABLE
    union all 
    select id, cast(stuff(stripped, patindex('%[^a-z]%', stripped), 1, '') as varchar(1024))
    from cte
    where patindex('%[^a-z]%', stripped) > 0
)
select * from cte
    where patindex('%[^a-z]%', stripped) = 0
order by id

Result:

>>id  stripped
>>1   qw
>>2   xxx
>>3 
>>4 
>>5   qqee

Solution 2

Declare @temp varchar(30)
Set @temp = 'A & B'
While PatIndex('%[^a-z]%', @Temp) > 0
Set @Temp = Stuff(@Temp, PatIndex('%[^a-z]%', @Temp), 1, '')

SELECT @id= (UPPER(SUBSTRING(@Temp,1,2)))+(UPPER(SUBSTRING((SELECT table.column2 FROM tablename WHERE tablename.column1 = @b),1,2))) + RIGHT('000000000' + CAST(@count as varchar(10)), 6)