Good! Did you notice the format? Here it is again:
2014-06-10 07:55:00.125
Let's analyze it. In PostgreSQL the date and time data type is timestamp
. It contains both date and time parts. The first part is the date and the second part is the time, reported to fractions of a second. The fractional value in both date and time data types, if given, must be in the range of 0 to 6 digits. The default precision for these data types is 6 digits.
The supported range in timestamp
is '4713-01-01 BC'
to '294276-12-31 AD'
. Note that the upper value for timestamp
is different than for date
(which is '5874897-12-31 AD'
).
timestamp
can also contain time zone:
'2018-05-23 07:55:12.534211+02'
The '+02'
refers to the timezone – in this case it means that we are two hours ahead of UTC. Time zone is optional. The timestamp
data type without time zone stores date and time in the local time of the database server (in our database it is UTC).
Now, let's look at a query:
SELECT id
FROM aircraft
WHERE withdrawn_timestamp < launched_timestamp;
The above query checks for typos in our table; we can make sure no aircraft was removed from service before it was launched.