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How do I calculate the time difference in milliseconds between two timestamps in Oracle?

sarsnake
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  • possible duplicate of [Calculate difference between 2 date / times in Oracle SQL](http://stackoverflow.com/questions/1096853/calculate-difference-between-2-date-times-in-oracle-sql) – Matt Ball Jul 23 '12 at 18:07
  • @Matt that answer doesn't demonstrate differences at the millisecond level – Daniel DiPaolo Jul 23 '12 at 18:07
  • Matt, the question that is "possibly a duplicate" doesn't answer what I asked. – sarsnake Jul 23 '12 at 18:08
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    Do you really mean "between two dates"? An Oracle `DATE` only has precision to the second. An Oracle `TIMESTAMP` has subsecond precision-- generally either millisecond or microsecond depending on the platform. – Justin Cave Jul 23 '12 at 18:10
  • thanks. Then I need the difference between 2 timestamps. Will update the question. – sarsnake Jul 23 '12 at 18:13
  • I'm kinda shocked and surprised that Oracle, (putatively) the world's leading RDMBS, doesn't have built-in date/time difference functions. How did anyone build this functionality into an Oracle-based application in decades past? – Dai Nov 14 '21 at 08:41

11 Answers11

99

When you subtract two variables of type TIMESTAMP, you get an INTERVAL DAY TO SECOND which includes a number of milliseconds and/or microseconds depending on the platform. If the database is running on Windows, systimestamp will generally have milliseconds. If the database is running on Unix, systimestamp will generally have microseconds.

  1  select systimestamp - to_timestamp( '2012-07-23', 'yyyy-mm-dd' )
  2*   from dual
SQL> /

SYSTIMESTAMP-TO_TIMESTAMP('2012-07-23','YYYY-MM-DD')
---------------------------------------------------------------------------
+000000000 14:51:04.339000000

You can use the EXTRACT function to extract the individual elements of an INTERVAL DAY TO SECOND

SQL> ed
Wrote file afiedt.buf

  1  select extract( day from diff ) days,
  2         extract( hour from diff ) hours,
  3         extract( minute from diff ) minutes,
  4         extract( second from diff ) seconds
  5    from (select systimestamp - to_timestamp( '2012-07-23', 'yyyy-mm-dd' ) diff
  6*           from dual)
SQL> /

      DAYS      HOURS    MINUTES    SECONDS
---------- ---------- ---------- ----------
         0         14         55     37.936

You can then convert each of those components into milliseconds and add them up

SQL> ed
Wrote file afiedt.buf

  1  select extract( day from diff )*24*60*60*1000 +
  2         extract( hour from diff )*60*60*1000 +
  3         extract( minute from diff )*60*1000 +
  4         round(extract( second from diff )*1000) total_milliseconds
  5    from (select systimestamp - to_timestamp( '2012-07-23', 'yyyy-mm-dd' ) diff
  6*           from dual)
SQL> /

TOTAL_MILLISECONDS
------------------
          53831842

Normally, however, it is more useful to have either the INTERVAL DAY TO SECOND representation or to have separate columns for hours, minutes, seconds, etc. rather than computing the total number of milliseconds between two TIMESTAMP values.

Justin Cave
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  • Sorry, not an Oracle expert myself. How would this cope with timezones/DST? All the answers here seem to use `24*60*60`, which is assuming that all days have 24H, which is wrong. In PostgreSQL, I would substract the two values returned from `EXTRACT(EPOCH FROM ...)`, but Oracle doesn't seem to have the equivalent. – Bruno Jul 23 '12 at 19:33
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    @Bruno - If the data types are `TIMESTAMP WITH TIME ZONE`, the interval that results from subtracting the two should take care of any time zone/ daylight savings time conversion. So subtracting a `TIMESTAMP WITH TIME ZONE` that is 5 am Eastern from a `TIMESTAMP WITH TIME ZONE` that is 2 am Pacific will result in an interval of 0 seconds. If you are just using a standard `TIMESTAMP` without a time zone, there is no time zone stored as part of the data so this sort of correction cannot be done. – Justin Cave Jul 23 '12 at 19:37
  • in `plsql` i tried this : `declare ta timestamp;` `select systimestamp - to_timestamp( '2012-07-23', 'yyyy-mm-dd' ) into ta from dual;` and it returns `Error(5,21): PL/SQL: ORA-00932: inconsistent datatypes: expected NUMBER got INTERVAL DAY TO SECOND` – Liza Jul 14 '15 at 02:31
  • @Kyrie - `ta` would need to be an `interval day to second` data type, not a `timestamp`. Subtracting one `timestamp` from another returns an `interval` not another `timestamp`. – Justin Cave Jul 14 '15 at 02:39
  • `"If the database is running on Windows, [it] will generally have milliseconds. If the database is running on Unix, [it] will generally have microseconds."`. I can't imagine how Oracle thinks this is acceptable – NTDLS Feb 28 '23 at 19:16
  • @NTLDS - Oracle gets the timestamp from the operating system so it is limited to the precision that the operating system supports. Windows (at least 10 years ago) generally only supported returning milliseconds so Oracle could only get milliseconds on Windows. I suppose Oracle could choose to truncate timestamps at the least precision that any operating system they support will return so that everyone had the same precision but the folks running on an OS that supports microseconds (or potentially nanoseconds) would not be happy about that. – Justin Cave Feb 28 '23 at 19:25
41

Here's a stored proc to do it:

CREATE OR REPLACE function timestamp_diff(a timestamp, b timestamp) return number is 
begin
  return extract (day    from (a-b))*24*60*60 +
         extract (hour   from (a-b))*60*60+
         extract (minute from (a-b))*60+
         extract (second from (a-b));
end;
/

Up Vote if you also wanted to beat the crap out of the Oracle developer who negated to his job!

BECAUSE comparing timestamps for the first time should take everyone an hour or so...

Brian McGinity
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20

Easier solution:

SELECT numtodsinterval(date1-date2,'day') time_difference from dates;

For timestamps:

SELECT (extract(DAY FROM time2-time1)*24*60*60)+ 
(extract(HOUR FROM time2-time1)*60*60)+
(extract(MINUTE FROM time2-time1)*60)+
extract(SECOND FROM time2-time1)
into diff FROM dual;

RETURN diff;
pat34515
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10
Select date1 - (date2 - 1) * 24 * 60 *60 * 1000 from Table;
Khaled.K
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phadaphunk
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  • Kind of a "WorkAround" but does the job – phadaphunk Jul 23 '12 at 18:09
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    I guess you meant **SELECT ( (timestamp1-1) - (timestamp2-1) ) * 86400000 from Table;** I like it even if I'd have chosen "+0" ;-) . However I think you lose the milliseconds precision as "-1" seems to convert TIMESTAMP to a DATE (which has no milliseconds).. – Myobis Oct 28 '14 at 17:10
3

I know that this has been exhaustively answered, but I wanted to share my FUNCTION with everyone. It gives you the option to choose if you want your answer to be in days, hours, minutes, seconds, or milliseconds. You can modify it to fit your needs.

CREATE OR REPLACE FUNCTION Return_Elapsed_Time (start_ IN TIMESTAMP, end_ IN TIMESTAMP DEFAULT SYSTIMESTAMP, syntax_ IN NUMBER DEFAULT NULL) RETURN VARCHAR2 IS
    FUNCTION Core (start_ IN TIMESTAMP, end_ IN TIMESTAMP DEFAULT SYSTIMESTAMP, syntax_ IN NUMBER DEFAULT NULL) RETURN VARCHAR2 IS
        day_ VARCHAR2(7); /* This means this FUNCTION only supports up to 99 days */
        hour_ VARCHAR2(9); /* This means this FUNCTION only supports up to 999 hours, which is over 41 days */
        minute_ VARCHAR2(12); /* This means this FUNCTION only supports up to 9999 minutes, which is over 17 days */
        second_ VARCHAR2(18); /* This means this FUNCTION only supports up to 999999 seconds, which is over 11 days */
        msecond_ VARCHAR2(22); /* This means this FUNCTION only supports up to 999999999 milliseconds, which is over 11 days */
        d1_ NUMBER;
        h1_ NUMBER;
        m1_ NUMBER;
        s1_ NUMBER;
        ms_ NUMBER;
        /* If you choose 1, you only get seconds. If you choose 2, you get minutes and seconds etc. */
        precision_ NUMBER; /* 0 => milliseconds; 1 => seconds; 2 => minutes; 3 => hours; 4 => days */
        format_ VARCHAR2(2) := ', ';
        return_ VARCHAR2(50);
    BEGIN
        IF (syntax_ IS NULL) THEN
            precision_ := 0;
        ELSE
            IF (syntax_ = 0) THEN
                precision_ := 0;
            ELSIF (syntax_ = 1) THEN
                precision_ := 1;
            ELSIF (syntax_ = 2) THEN
                precision_ := 2;
            ELSIF (syntax_ = 3) THEN
                precision_ := 3;
            ELSIF (syntax_ = 4) THEN
                precision_ := 4;
            ELSE 
                precision_ := 0;
            END IF;
        END IF;
        SELECT EXTRACT(DAY FROM (end_ - start_)) INTO d1_ FROM DUAL;
        SELECT EXTRACT(HOUR FROM (end_ - start_)) INTO h1_ FROM DUAL;
        SELECT EXTRACT(MINUTE FROM (end_ - start_)) INTO m1_ FROM DUAL;
        SELECT EXTRACT(SECOND FROM (end_ - start_)) INTO s1_ FROM DUAL;
        IF (precision_ = 4) THEN
            IF (d1_ = 1) THEN
                day_ := ' day';
            ELSE
                day_ := ' days';
            END IF;
            IF (h1_ = 1) THEN
                hour_ := ' hour';
            ELSE
                hour_ := ' hours';
            END IF;
            IF (m1_ = 1) THEN
                minute_ := ' minute';
            ELSE
                minute_ := ' minutes';
            END IF;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := d1_ || day_ || format_ || h1_ || hour_ || format_ || m1_ || minute_ || format_ || s1_ || second_;
            RETURN return_;
        ELSIF (precision_ = 3) THEN
            h1_ := (d1_ * 24) + h1_;
            IF (h1_ = 1) THEN
                hour_ := ' hour';
            ELSE
                hour_ := ' hours';
            END IF;
            IF (m1_ = 1) THEN
                minute_ := ' minute';
            ELSE
                minute_ := ' minutes';
            END IF;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := h1_ || hour_ || format_ || m1_ || minute_ || format_ || s1_ || second_;
            RETURN return_;
        ELSIF (precision_ = 2) THEN
            m1_ := (((d1_ * 24) + h1_) * 60) + m1_;
            IF (m1_ = 1) THEN
                minute_ := ' minute';
            ELSE
                minute_ := ' minutes';
            END IF;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := m1_ || minute_ || format_ || s1_ || second_;
            RETURN return_;
        ELSIF (precision_ = 1) THEN
            s1_ := (((((d1_ * 24) + h1_) * 60) + m1_) * 60) + s1_;
            IF (s1_ = 1) THEN
                second_ := ' second';
            ELSE
                second_ := ' seconds';
            END IF;
            return_ := s1_ || second_;
            RETURN return_;
        ELSE
            ms_ := ((((((d1_ * 24) + h1_) * 60) + m1_) * 60) + s1_) * 1000;
            IF (ms_ = 1) THEN
                msecond_ := ' millisecond';
            ELSE
                msecond_ := ' milliseconds';
            END IF;
            return_ := ms_ || msecond_;
            RETURN return_;
        END IF;
    END Core;
BEGIN
    RETURN(Core(start_, end_, syntax_));
END Return_Elapsed_Time;

For example, if I called this function right now (12.10.2018 11:17:00.00) using Return_Elapsed_Time(TO_TIMESTAMP('12.04.2017 12:00:00.00', 'DD.MM.YYYY HH24:MI:SS.FF'),SYSTIMESTAMP), it should return something like:

47344620000 milliseconds
iamdoubz
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1

Better to use procedure like that:

CREATE OR REPLACE FUNCTION timestamp_diff
(
start_time_in TIMESTAMP
, end_time_in TIMESTAMP
)
RETURN NUMBER
AS
l_days NUMBER;
l_hours NUMBER;
l_minutes NUMBER;
l_seconds NUMBER;
l_milliseconds NUMBER;
BEGIN
SELECT extract(DAY FROM end_time_in-start_time_in)
, extract(HOUR FROM end_time_in-start_time_in)
, extract(MINUTE FROM end_time_in-start_time_in)
, extract(SECOND FROM end_time_in-start_time_in)
INTO l_days, l_hours, l_minutes, l_seconds
FROM dual;

l_milliseconds := l_seconds*1000 + l_minutes*60*1000 + l_hours*60*60*1000 + l_days*24*60*60*1000;
RETURN l_milliseconds;

END;

You can check it by calling:

SELECT timestamp_diff (TO_TIMESTAMP('12.04.2017 12:00:00.00', 'DD.MM.YYYY HH24:MI:SS.FF'), 
                      TO_TIMESTAMP('12.04.2017 12:00:01.111', 'DD.MM.YYYY HH24:MI:SS.FF')) 
            as milliseconds
    FROM DUAL;
Konki
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0

The timestamp casted correctly between formats else there is a chance the fields would be misinterpreted.

Here is a working sample that is correct when two different dates (Date2, Date1) are considered from table TableXYZ.

SELECT ROUND (totalSeconds / (24 * 60 * 60), 1) TotalTimeSpendIn_DAYS,
       ROUND (totalSeconds / (60 * 60), 0) TotalTimeSpendIn_HOURS,
       ROUND (totalSeconds / 60) TotalTimeSpendIn_MINUTES,
       ROUND (totalSeconds) TotalTimeSpendIn_SECONDS
  FROM (SELECT ROUND (
                    EXTRACT (DAY FROM timeDiff) * 24 * 60 * 60
                  + EXTRACT (HOUR FROM timeDiff) * 60 * 60
                  + EXTRACT (MINUTE FROM timeDiff) * 60
                  + EXTRACT (SECOND FROM timeDiff))
                  totalSeconds,
          FROM (SELECT TO_TIMESTAMP (
                            TO_CHAR (Date2,
                                     'yyyy-mm-dd HH24:mi:ss')
                          - 'yyyy-mm-dd HH24:mi:ss'),
                       TO_TIMESTAMP (
                          TO_CHAR (Date1,
                                   'yyyy-mm-dd HH24:mi:ss'),
                          'yyyy-mm-dd HH24:mi:ss')
                          timeDiff
                  FROM TableXYZ))
Sreesankar
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0

Above one has some syntax error, Please use following on oracle:

SELECT ROUND (totalSeconds / (24 * 60 * 60), 1) TotalTimeSpendIn_DAYS,
  ROUND (totalSeconds      / (60 * 60), 0) TotalTimeSpendIn_HOURS,
  ROUND (totalSeconds      / 60) TotalTimeSpendIn_MINUTES,
  ROUND (totalSeconds) TotalTimeSpendIn_SECONDS
FROM
  (SELECT ROUND ( EXTRACT (DAY FROM timeDiff) * 24 * 60 * 60 + EXTRACT (HOUR FROM timeDiff) * 60 * 60 + EXTRACT (MINUTE FROM timeDiff) * 60 + EXTRACT (SECOND FROM timeDiff)) totalSeconds
  FROM
    (SELECT TO_TIMESTAMP(TO_CHAR( date2 , 'yyyy-mm-dd HH24:mi:ss'), 'yyyy-mm-dd HH24:mi:ss') - TO_TIMESTAMP(TO_CHAR(date1, 'yyyy-mm-dd HH24:mi:ss'),'yyyy-mm-dd HH24:mi:ss') timeDiff
    FROM TABLENAME
    )
);
Vino
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0

I) if you need to calculate the elapsed time in seconds between two timestamp columns try this:

SELECT 
    extract ( day from (end_timestamp - start_timestamp) )*86400 
    + extract ( hour from (end_timestamp - start_timestamp) )*3600 
    + extract ( minute from (end_timestamp - start_timestamp) )*60 
    + extract ( second from (end_timestamp - start_timestamp) ) 
FROM table_name

II) if you want to just show the time difference in character format try this:

SELECT to_char (end_timestamp - start_timestamp) FROM table_name
David Buck
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0

I've posted here some methods to convert interval to nanoseconds and nanoseconds to interval. These methods have a nanosecond precision.

You just need to adjust it to get milliseconds instead of nanoseconds.

A shorter method to convert interval to nanoseconds.

SELECT (EXTRACT(DAY FROM (
    INTERVAL '+18500 09:33:47.263027' DAY(5) TO SECOND --Replace line with desired interval --Maximum value: INTERVAL '+694444 10:39:59.999999999' DAY(6) TO SECOND(9) or up to 3871 year
) * 24 * 60) * 60 + EXTRACT(SECOND FROM (
    INTERVAL '+18500 09:33:47.263027' DAY(5) TO SECOND --Replace line with desired interval
))) * 100 AS MILLIS FROM DUAL;

MILLIS
1598434427263.027
0

I know that many people finding this solution simple and clear:

create table diff_timestamp (
f1 timestamp
, f2 timestamp);

insert into diff_timestamp values(systimestamp-1, systimestamp+2);
commit;

select cast(f2 as date) - cast(f1 as date) from diff_timestamp;

bingo!

rethab
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  • While that works, you are throwing away precision and accuracy. Precision cause DATE only goes down to seconds, where as TIMESTAMP supports fractional seconds. And accuracy as DATE does NOT support timezones while TIMESTAMP does. 2 Timestamps that both read "07:25:17.123" might not be the same time when they are from different timezones. – ABaumstumpf May 11 '21 at 08:49