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When I create the test case below, the filtered index is always chosen, even on the different versions of SQL Server with different configuration.

create table #t (id int not null identity(1,1) primary key clustered
    ,value varchar(10) not null default (convert(varchar(10), convert(varchar(36), newid())))
    ,status tinyint default (0)
)

insert into #t (value, status)
values (default, 3), (default, 2) -- repeat this however you like to populate

select * from #t as t

create index idxT_Status on #t (status) include (value)
create index idxT_StatusF on #t (status) include (value) where status = 2

create procedure #p as
begin
    insert into #t (value, status)
    select value, 33 from #t where status = 2

    update t
    set status = 22
    from #t as t
    where status = 2
end

select * from #t as t where status = 2

begin tran

insert into #t (value, status)
select value, 33 from #t where status = 2

However, I have a very similar scenario in the live application which I am working with where in the presence of the full index, the filtered index is ignored. If I drop the full index, then the plan happily chooses the filtered index. I totally get it that with only about 20,000 records in the table it makes very little difference in terms of execution time, which is borderline negligible 0-16 ms with full or filtered index, just trying to get to the bottom of it.

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