Referring to a Column Alias in a WHERE Clause

Question

SELECT logcount, logUserID, maxlogtm
   , DATEDIFF(day, maxlogtm, GETDATE()) AS daysdiff
FROM statslogsummary
WHERE daysdiff > 120

I get

Answer 1

For me, the simplest way to use ALIAS in WHERE class is to create a subquery and select from it instead.

Example:

WITH Q1 AS (
    SELECT LENGTH(name) AS name_length,
    id,
    name
    FROM any_table
)

SELECT id, name, name_length form Q1 where name_length > 0

Cheers, Kel