Postgres function to check if something is null

Question

Select
   id,
   username,
   is_null(email) AS has_email,
FROM
  users
;

I want to write the above query, but instead of returning the email, I only want it to return whether there is an email. Is there a way to do that?

Why do you consider an email that is null to be a sign that there is an email? Don't you rather want to test for "not null"? — user330315
– user330315, Commented Nov 23, 2014 at 20:06
This is all documented in the manual btw: postgresql.org/docs/current/static/functions-comparison.html — user330315
– user330315, Commented Nov 23, 2014 at 20:08

Clément Prévost · Accepted Answer · 2014-11-23 20:27:37Z

2

Try this

Select
   id,
   username,
   email IS NOT NULL AS has_email
FROM
   users
;

Edit: changed IS NULL to IS NOT NULL

user330315

answered Nov 23, 2014 at 19:40

Clément Prévost

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