Rounding hour and minute from time stamp to the closest hour - response (1) by dnoeth

Hi Ozge,
ROUND always results in a DATE (blame Oracle), so you can't use it in that case.
What's the datatype of solved_at_ts and what datatype do you need as result? When you add 30 minutes you could simply extract the hour, e.g. 

EXTRACT(HOUR FROM solved_at_ts + INTERVAL '30' MINUTE)