Question

declare @t1 Table
(
a1 int
)

insert into @t1 
select top 10 AnimalID from Animal 

--select * from @t1 

declare @t2 table
(
dogs int null
)

update @t2
set dogs = (Select COUNT(*) from @t1)

———> The out put it gives me is just 0

Answer 1

It is because you are creating your table, and updating it, but its empty.

Change

update @t2 set dogs = (Select COUNT(*) from @t1)

For

declare @c int

select @c = COUNT(*) from @t1

insert into @t2 (dogs) values (@c)