I have a DATE
column that I want to round to the next-lower 10 minute interval in a query (see example below).
I managed to do it by truncating the seconds and then subtracting the last digit of minutes.
WITH test_data AS (
SELECT TO_DATE('2010-01-01 10:00:00', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2010-01-01 10:05:00', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2010-01-01 10:09:59', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2010-01-01 10:10:00', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2099-01-01 10:00:33', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
)
-- #end of test-data
SELECT
d, TRUNC(d, 'MI') - MOD(TO_CHAR(d, 'MI'), 10) / (24 * 60)
FROM test_data
And here is the result:
01.01.2010 10:00:00 01.01.2010 10:00:00
01.01.2010 10:05:00 01.01.2010 10:00:00 01.01.2010 10:09:59 01.01.2010 10:00:00 01.01.2010 10:10:00 01.01.2010 10:10:00 01.01.2099 10:00:33 01.01.2099 10:00:00
Works as expected, but is there a better way?
EDIT:
I was curious about performance, so I did the following test with 500.000 rows and (not really) random dates. I am going to add the results as comments to the provided solutions.
DECLARE
t 开发者_Go百科 TIMESTAMP := SYSTIMESTAMP;
BEGIN
FOR i IN (
WITH test_data AS (
SELECT SYSDATE + ROWNUM / 5000 d FROM dual
CONNECT BY ROWNUM <= 500000
)
SELECT TRUNC(d, 'MI') - MOD(TO_CHAR(d, 'MI'), 10) / (24 * 60)
FROM test_data
)
LOOP
NULL;
END LOOP;
dbms_output.put_line( SYSTIMESTAMP - t );
END;
This approach took 03.24 s
.
select
trunc(sysdate, 'mi')
- numtodsinterval(mod(EXTRACT(minute FROM cast(sysdate as timestamp)), 10), 'minute')
from dual;
or even
select
trunc(sysdate, 'mi')
- mod(EXTRACT(minute FROM cast(sysdate as timestamp)), 10) / (24 * 60)
from dual;
I generally hate doing date -> character -> date conversions when it's not necessary. I'd rather use numbers.
select trunc((sysdate - trunc(sysdate))*60*24,-1)/(60*24)+trunc(sysdate) from dual;
This extracts the minutes from the current day, truncates them down to the 10-minute interval, and then adds them back in to make it a date again. Of course, you can replace sysdate with whatever date you want. It trusts implicit conversions a lot more than I want but at least it'll work for any NLS date format.
You could take the returned value as a string and substring the left side up to the last minute digit and replace it with a 0
. I wouldn't exactly say thats better unless you provide some kind of metric.
Not necessarily any better, but another method:
WITH test_data AS (
SELECT TO_DATE('2010-01-01 10:00:00', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2010-01-01 10:05:00', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2010-01-01 10:09:59', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2010-01-01 10:10:00', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
UNION SELECT TO_DATE('2099-01-01 10:00:33', 'YYYY-MM-DD HH24:MI:SS') d FROM dual
)
-- #end of test-data
SELECT
d, TRUNC(d) + FLOOR((d-TRUNC(d))*24*6)/(24*6)
FROM test_data
Another method,
select my_date - mod( (my_date-trunc(my_date))*24*60, 10)/24/60
from (
select sysdate my_date from dual
);
An alternative that might be quicker as it removes the call to trunc.
select my_date - mod( (my_date-to_date('1970', 'yyyy'))*24*60, 10)/24/60
from (
select sysdate my_date from dual
);
To return the next upper 10 minute interval, I used the following query. I hope it'll be useful because I couldn't simply do a
trunc(sysdate, 'mi') + mod(EXTRACT(minute FROM cast(sysdate as timestamp)), 10) / (24 * 60)
I did this and it worked for me.
select
case when mod(EXTRACT(minute FROM cast(sysdate as timestamp)),5) between 1 and 4
then trunc(sysdate,'mi')+((5*TRUNC(EXTRACT(minute FROM cast(sysdate as timestamp))/5,
0)+5)-EXTRACT(minute FROM cast(sysdate as timestamp)))/1440
else trunc(sysdate,'mi')
end
from dual
This is based on this post.
I think to solve this there's a much easier and faster way to round to a next lower 10 seconds, 1 Minute, 10 Minute etc. interval. Try to manipulate your timestamp as a string using SUBSTR() like this:
SELECT
SUBSTR(datetime(d),1,18)||'0' AS Slot10sec,
SUBSTR(datetime(d),1,17)||'00' AS Slot1min,
SUBSTR(datetime(d),1,15)||'0:00' AS Slot10min,
SUBSTR(datetime(d),1,14)||'00:00' AS Slot1h,
MY_VALUE
FROM MY_TABLE;
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