A useful function which used to split data by ',' from one column

drop FUNCTION cgns_02.f_splitstr
@
CREATE FUNCTION cgns_02.f_splitstr
(
 srcsql varchar(3999)  
)
  RETURNS varchar(3999)
 
BEGIN ATOMIC
/*******************************************
*function name  : split string from one column 
*function create time : 2016-11-22



*******************************************/
return 
with n(str, ori, pos) as (
values (to_char(srcsql)||',', 1,locate(',',to_char(srcsql)||','))
union all
select  str,  pos+length(','), locate(',', str, pos+length(','))
from n
where locate(',', str,pos+length(','))>0) ,
temp as(
select distinct substr(str, ori, pos-ori) as result from n)
select listagg(result,',') from temp;

END