Conditional ordering in SQL Server - sql-server

Question

Table T:
ID | Name | Days
ID is the PK.
I do want to select * from T, order by ID descending, but on TOP to be those entries which have the ID between 1000 and 1004
select *
from T
order by Id descending // something like a *case*?
1004 - 1st / 1003 2nd / 1002 3rd / 1001 4th / 1000 5nd ... and then 6th should be the max Id, and after this all descending excepting the Ids between 1000 - 1004 which we already displayed on the TOP.
I would like to know also the linq statement.

Answer 1

SELECT *
FROM (VALUES (998), (999), (1000), (1001), (1002), (1003), (1004)) AS T(ID)
ORDER BY CASE
WHEN T.ID BETWEEN 1000 AND 1004 THEN 1
ELSE 2
END
, ID DESC;
Took sample data from Sick's answer.
How does this work?
It checks whether your ID is matching your criteria and assign it a
value of 1
Everything else will have 2
It will sort by this value first
Your IDs with matching criteria will ALWAYS come first
Then we sort leftovers by ID in DESC order
Output:
╔══════╗
║ ID ║
╠══════╣
║ 1004 ║
║ 1003 ║
║ 1002 ║
║ 1001 ║
║ 1000 ║
║ 999 ║
║ 998 ║
╚══════╝
I've made additional example, which generates 676.800 rows in our DB:
;WITH TestTable (ID)
AS (
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL))
FROM sys.objects
CROSS JOIN sys.schemas
)
SELECT *
FROM TestTable AS T
ORDER BY CASE
WHEN T.ID BETWEEN 1000 AND 1004 THEN 1
ELSE 2
END
, ID DESC;
That's its result:
╔════════╗
║ ID ║
╠════════╣
║ 1004 ║
║ 1003 ║
║ 1002 ║
║ 1001 ║
║ 1000 ║
║ 676800 ║
║ 676799 ║
║ 676798 ║
║ 676797 ║
║ 676796 ║
║ 676795 ║
║ ... ║
║ 1006 ║
║ 1005 ║
║ 999 ║
║ 998 ║
║ ... ║
║ 1 ║
╚════════╝

Answer 2

Try this
select *
from T
order by case when ID between 1000 and 1004 then -100000 else id end,ID desc
Here -100000 is s random low value
Example :
SELECT *
FROM (VALUES (998),
(999),
(1000),
(1001),
(1002),
(1003),
(1004) ) tc (id)
ORDER BY CASE
WHEN ID BETWEEN 1000 AND 1004 THEN -100000
ELSE id
END,
ID DESC

Answer 3

SELECT column_name, column_name
FROM table_name
ORDER BY column_name ASC|DESC, column_name ASC|DESC;