Q:

LAST_DAY function in postgres

Is there any function(s) in postgres equivalent to Oracle function LAST_DAY().
I need to get last day in postgres (including month and year)

A:

Well, In postgres, it seems there's no such function equivalent to LAST_DAY() available in oracle. 
If you need to, you can have your own in the following ways as a
Select Query
SELECT (date_trunc('MONTH', now()) + INTERVAL '1 MONTH - 1 day')::date;

plsql Function
        CREATE OR REPLACE FUNCTION last_day(date)
        RETURNS date AS
        $$
        SELECT (date_trunc('MONTH', $1) + INTERVAL '1 MONTH - 1 day')::date;
        $$ LANGUAGE 'sql'
        IMMUTABLE STRICT;

Hope this helps. 

