将秒转换为 yyyy-mm-dd hh:mm:ss PostgreSQL

Question

I am new to PostgreSQL sql and now working on an already existing database. I have a column called value in a table and it contains datetime stamp in seconds. So I am looking for way I can convert those seconds to yyyy-mm-dd hh:mm:ss in a Postgres database. I tried the following:

SELECT  TO_CHAR('1444646136079 second'::interval, 'yyyy-mm-dd HH24:MI:SS')

1444646136079 is the value I would like to convert But I am getting the following error:

ERROR: interval field value out of range: "1444646136079 second"

Answer 1

An interval is not a "timestamp".

The to_timestamp() function accepts seconds as an input and can convert that to a proper timestamp. I believe your 1444646136079 is in fact milli seconds, not seconds:

select to_char(to_timestamp(1444646136079 / 1000), 'yyyy-mm-dd HH24:MI:SS')

returns:

2015-10-12 12:35:36

Answer 2

You can try it too -

select to_date(to_timestamp(1344646136069 / 1000)::TEXT, 'yyyy-mm-dd HH24:MI:SS');

select to_date(to_timestamp(1344646136069 / 1000)::TEXT, 'YYYY-MM-DD HH:MI:SS');

Output :

11.08.2012 00:00:00
11.08.2012 00:00:00