Hi,
I'm trying to truncate timestamp value to hour and/or minute precision. I combined cast and extract functions as:
Problem: Truncate '2013-08-12 23:59:59' to '2013-08-12 23:00:00'
select cast(timestamp '2013-08-12 23:59:59' as date)||' '||extract(hour from timestamp '2013-08-12 23:59:59')||':00:00';
Output: 2013-08-12 23:00:00
But this is expensive because of repeated function calls. Is there any faster and built-in function?