使用PostgreSQL从Unix时间戳中提取日期，月份，年份和月份名称

Question

I use postgres for the rails app and I have a unix timestamp in postgresql db. I have a requirement to select and group by the dd-mm-yyyy and by month name .

Consider I have the following unix timestamp

1425148200

and I would need to change this to datetime and I used to_timestamp which returned

2015-02-28 18:30:00 UTC

and I tried to convert the datetime to local timezone using

::timestamp without time zone AT TIME ZONE 'IST'

but that did not give time in required timezone and instead it returned

2015-02-28 16:30:00 UTC

and I tried to get the date part using ::date which returned

Sat, 28 Feb 2015

So please help me get the dd-mm-yyyy in specified timezone and month name(March) from the unix timestamp.

Thanks in Advance!

Answer 1

select to_char(to_timestamp('1425148200')::timestamptz at time zone 'UTC-5:30','DD-MM-YYYY & of course Month')

01-03-2015 & of course March

It is postgres mistake I guess according to http://www.postgresql.org/docs/7.2/static/timezones.html