The number of differences in a column

Question

I would like to retrieve a column of how many differences in letters in each row. For instance

If you have a a value \"test\" and another row has a value \"testing \", t

Answer 1

create table #temp
(
id int,
value varchar(30),
category int
)

insert into #temp
select 1,'test',1
union all
select 2,'testing',1
union all
select 1,'Candy',2
union all
select 2,'Ca',2

;with cte
as
(
select id,value,category,lead(value) over (partition by category order by id) as nxtvalue
from #temp
)
select id,value,category,len(replace(nxtvalue,value,'')) as differences
from cte