Question

I have these simple SQL statements:

SELECT     COUNT(ID) AS Expr1
FROM         Table1
UNION
SELECT     COUNT(ID) AS Expr2
FROM         Table1 AS Table1_1
WHERE     (UPDATED > CREATED)
UNION
SELECT     COUNT(DISTINCT DATEPART(year, UPDATED)) AS Expr3
FROM         Table1 AS Table1_2

I want to show results as:

Expr1     Expr2    Expr3
-----     -----    -----
5           3         2

How to do that ? I understand that UNION is more reliable and faster than using OR in WHERE clause.

Answer 1

You cannot do this with UNION – that will give you a union of rows – not columns.

For your requirement, try something like this:

SELECT 
    Expr1 = (SELECT COUNT(ID) FROM Table1),
    Expr2 = (SELECT COUNT(ID) FROM Table1 WHERE UPDATED > CREATED),
    Expr3 = (SELECT COUNT(DISTINCT DATEPART(year, UPDATED)) FROM Table1)

That will give you one row with three columns, containing the values you’re looking for.