Name	Description
current_time	Current time (start of current transaction).
date_diff(part, starttime, endtime)	The number of partition boundaries between the times.
date_part(part, time)	Get subfield (equivalent to extract).
date_sub(part, starttime, endtime)	The number of complete partitions between the times.
datediff(part, starttime, endtime)	Alias of date_diff. The number of partition boundaries between the times.
datepart(part, time)	Alias of date_part. Get subfield (equivalent to extract).
datesub(part, starttime, endtime)	Alias of date_sub. The number of complete partitions between the times.
extract(part FROM time)	Get subfield from a time.
get_current_time()	Current time (start of current transaction).
make_time(bigint, bigint, double)	The time for the given parts.