Logic needed for increment value

Question

HI,
This function returns me if i pass 'ABC01' it will return 'ABC02' like if i pass
'ABC55' it will return 'ABC56'.
But my requirment is i need to pass value from 01 to 99.
so if i pass 'ABC99' it sud return ''ABC01'.
so the sequence is from 01 to 99.And after 99 it will again start from 01.
create or replace function get_next_value
string_1 in varchar2
return varchar2
as
v_string_1 number(10);
v_string_2 varchar2(10);
begin
select to_number(substr(string_1,4))+1 into v_string_1 from dual;
if length(v_string_1)=1 then
v_string_2:=substr(string_1,1,4)||v_string_1;
return v_string_2;
else
v_string_2:=substr(string_1,1,3)||v_string_1;
return v_string_2;
end if;
end;
test sript
select get_next_value('ABC01') from dual
select get_next_value('ABC55') from dual
Thanks,
Lony

Answer 1

create or replace function get_next_value
string_1 in varchar2
return varchar2
as
v_string_1 number(10);
v_string_2 varchar2(10);
begin
select to_number(substr(string_1,4))+1 into v_string_1 from dual;
if length(v_string_1)=1 then
v_string_2:=substr(string_1,1,4)||v_string_1;
return v_string_2;
else
v_string_2:=substr(string_1,1,3)||v_string_1;
if v_string_1 = 100 then
   return substr(string_1,1,3)||'01';
end if;
return v_string_2;
end if;
end;
select get_next_value('ABC01') from dual;
select get_next_value('ABC99') from dual;
GET_NEXT_VALUE('ABC01')                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
ABC02                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
1 rows selected
GET_NEXT_VALUE('ABC99')                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
ABC01