SQL - Is it possible to join a table to a resultset created by several select/union-alls?

Question

I'm trying to find a workaround (hack) to some limitations preventing me from using a temporary table or a table variable in my SQL query.

I have a real table (technically it's a derived table that results from an UNPIVOT of a poorly designed table) which lacks several necessary fields. I need to hardcode these fields into the result until we can cleanup the database issue.

Given a table like:

tblEntity
ID | Name
 1 |  One
 2 |  Two

I need to join several fields such as:

ID | Order
 1 |     2
 2 |     1

The join would result in:

ID | Name | Order
 1 |  One |     2
 2 |  Two |     1

My question is: can I join tblEntity to a resultset created like:

SELECT 1, 2
UNION ALL
SELECT 2, 1

Is it possible to join? If so, what is the syntax?

Answer 1

select te.*, t.Ord from tblEntity te
inner join (
    SELECT 1 as Id, 2 as Ord
    UNION ALL
    SELECT 2, 1
) t on te.ID = t.Id

Answer 2

Making a few assumptions, this would do it:

SELECT en.ID, en.Name, xx.OrderBy
 from tblEntity en
  inner join (select 1 Id, 2 OrderBy
              union all
              select 2,1) xx
   on xx.Id = en.ID

Answer 3

In SQL-Server 2008, it's also possible to use Table Value Constructors:

CREATE TABLE #tblEntity
( ID INT
, Name CHAR(10)
) ;

INSERT INTO #tblEntity
  (ID, Name)
VALUES
  ( 1, 'One' ) ,
  ( 2, 'Two' ) ;

SELECT 
    t.ID, t.Name, o.Ordr AS "Order"
FROM 
        #tblEntity AS t
    JOIN
        ( VALUES
             (1,2)
           , (2,1)
        ) AS o(ID, Ordr)
      ON o.ID = t.ID ;

You can test the above in: data.stackexchange.com

Answer 4

Many ways of doing this e.g.

WITH T1 (Id, "Order")
     AS 
     (
      SELECT 1, 2
      UNION ALL
      SELECT 2, 1
     )
SELECT e.*, T1."Order"
  FROM tblEntity e 
       JOIN T1 
          ON e.Id = T1.Id;

e.g. 2

SELECT e.*, T1."Order"
  FROM tblEntity e 
       JOIN (
             VALUES (1, 2), 
                    (2, 1)
            ) AS T1 (Id, "Order")
          ON e.Id = T1.Id;

e.g. 3

WITH T1 
     AS 
     (
      SELECT * 
        FROM (
              VALUES (1, 2), 
                     (2, 1)
             ) AS T (Id, "Order")
     )
SELECT e.*, T1."Order"
  FROM tblEntity e 
       JOIN T1 
          ON e.Id = T1.Id;

...and so on.