Group by with Unix time stamps - sql

Question

I am trying write a query where time stamps are in Unix format.
The objective of the query is group by these time stamps in five minute segments and to count each unique Id in those segments.
Is there a simple way of doing this?
The result looking for this
Time_utc Id count
25/07/2019 1600 1 3
25/07/2019 1600 2 1
25/07/2019 1605 1 4

Answer 1

You haven't shown data, so as a starting point you can group the Unix timestamps by dividing by 300 (for 5 minutes worth of seconds):
select 300 * floor(unix_ts/300) as unix_five_minute,
timestamp '1970-01-01 00:00:00 UTC'
+ (300*floor(unix_ts/300)) * interval '1' second as oracle_timestamp,
count(*)
from cte2
group by floor(unix_ts/300);
or if you have millisecond precision adjust by a factor of 1000:
select 300000 * floor(unix_ts/300000) as unix_five_minute,
timestamp '1970-01-01 00:00:00 UTC'
+ (300*floor(unix_ts/300000)) * interval '1' second as oracle_timestamp,
count(*)
from cte2
group by floor(unix_ts/300000);
Demo using made-up data generated from current time:
-- CTEs to generate some sample data
with cte1 (oracle_interval) as (
select systimestamp - level * interval '42' second
- timestamp '1970-01-01 00:00:00.0 UTC'
from dual
connect by level <= 30
),
cte2 (unix_ts) as (
select trunc(
extract(day from oracle_interval) * 86400000
+ extract(hour from oracle_interval) * 3600000
+ extract(minute from oracle_interval) * 60000
+ extract(second from oracle_interval) * 1000
)
from cte1
)
-- actual query
select 300000 * floor(unix_ts/300000) as unix_five_minute,
timestamp '1970-01-01 00:00:00 UTC'
+ (300*floor(unix_ts/300000)) * interval '1' second as oracle_timestamp,
count(*)
from cte2
group by floor(unix_ts/300000);
UNIX_FIVE_MINUTE ORACLE_TIMESTAMP COUNT(*)
---------------- ------------------------- ----------------
1564072500000 2019-07-25 16:35:00.0 UTC 7
1564072200000 2019-07-25 16:30:00.0 UTC 7
1564071600000 2019-07-25 16:20:00.0 UTC 4
1564071900000 2019-07-25 16:25:00.0 UTC 8
1564072800000 2019-07-25 16:40:00.0 UTC 4
Unix time stamps such as 155639.600 or 155639.637
Those are unusual values; Unix/epoch times are usually 10-digit numbers, or 13 digits for millisecond precision. Assuming (or rather, guessing) that they are tenths of a second for some reason:
-- CTE for sample data
with cte (unix_ts) as (
select 155639.600 from dual
union all
select 155639.637 from dual
)
-- actual query
select 300 * floor(unix_ts*10000/300) as unix_five_minute,
timestamp '1970-01-01 00:00:00 UTC'
+ (300*floor(unix_ts*10000/300)) * interval '1' second as oracle_timestamp,
count(*)
from cte
group by floor(unix_ts*10000/300);
UNIX_FIVE_MINUTE ORACLE_TIMESTAMP COUNT(*)
---------------- ------------------------- ----------------
1556396100 2019-04-27 20:15:00.0 UTC 1
1556395800 2019-04-27 20:10:00.0 UTC 1
The 10000/300 could be simplified to 100/3, but I think it's clearer left as it is.