Character filter function, filter repeating string

The actual effect is not big, sometimes use, save as later reference. If the predestined person sees, asks to propose the optimization plan

1 Use[Master]
2GO
3/** * * * object:userdefinedfunction [dbo].    [Charfilter] Script date:04/06/2016 17:20:16 * * * * **/
4SETAnsi_nulls on
5GO
6SETQuoted_identifier on
7GO
8--=========================================================
9--filter the repeating character in the string Charfilter @str as the input string,
Ten@symSeparator
One--The character length is allocated according to the actual demand
A --=========================================================
-CREATEFUNCTION[dbo].[Charfilter](@strvarchar(8000),@symvarchar( -))
-RETURNSvarchar(8000)
the as
-BEGIN
-Declare@returnvarchar(8000),@retvarchar(8000)
-Select@str=@str+','
+ whilecharindex(@sym,@str)>0
-begin
+ Select@ret=substring(@str,1,charindex(@sym,@str)-1)
A
atSelect@return=IsNull(@return+@sym,"')+@ret
-
-Select @str=Replace(@str,@ret+@sym,"')
-End
-RETURN@return

- END

Character filter function, filter repeating string