How to get the number of days in a month?

Question

I am trying to get the following in Postgres:

select day_in_month(2);

Expected output:

28

Is there any bu

Answer 1

You can write a function:

CREATE OR REPLACE FUNCTION get_total_days_in_month(timestamp)
RETURNS decimal
IMMUTABLE
AS $$
  select cast(datediff(day, date_trunc('mon', $1), last_day($1) + 1) as decimal)
$$ LANGUAGE sql;