Refer to a column name alias in the WHERE clause

Question

I have written down this query in postgres sql with column alias it is working fine:

select email as e from users

It displays me result under e column alias but when I fire where condition with e then it shows this error:

select email as e from users where e = 'jaskaransingh@demo.com'

ERROR: column "e" does not exist

Why so? How we can use alias in where condition?

Any updates for a solution ?:) – Давид Шико May 08 '22 at 16:10 — Давид Шико, May 08 '22 at 16:10

potashin · Answer 1 · 2018-12-17T11:19:20.047

19

where is evaluated before select, so you can't use alias declared in select in where clause.

edited Dec 17 '18 at 11:19

answered Jun 16 '15 at 12:44

potashin

3

This is correct but makes me sad. Is there a good reason for this? Would be so useful to be able to refer to aliases in the `where` clause. – mitchus Oct 06 '20 at 13:47

1 Answers1