How to handle leap seconds in Oracle - oracle

Tonight there is going to be a leap second added to the clocks and there will be 61 seconds in the last minute of the last hour of the day.
2015-06-30 23:59:60
However, Oracle only supports up to 60 seconds in a minute:
TO_DATE( '2015-06-30 23:59:60', 'YYYY-MM-DD HH24:MI:SS' )
Errors with:
ORA-01852: seconds must be between 0 and 59
and
SELECT TO_DATE( '2015-06-30 23:59:59', 'YYYY-MM-DD HH24:MI:SS' ) + INTERVAL '1' SECOND AS Incr_Second_Before,
TO_DATE( '2015-07-01 00:00:00', 'YYYY-MM-DD HH24:MI:SS' ) - INTERVAL '1' SECOND AS Decr_Second_After
FROM DUAL
Gives the output:
| INCR_SECOND_BEFORE | DECR_SECOND_AFTER |
|------------------------|------------------------|
| July, 01 2015 00:00:00 | June, 30 2015 23:59:59 |
Is there any way to handle a leap second in Oracle?

From MOS-
Insert leap seconds into a timestamp column fails with ORA-01852 (Doc
ID 1553906.1)
APPLIES TO:
Oracle Database - Enterprise Edition - Version 8.1.7.4 and later
Oracle Database - Standard Edition - Version 8.1.7.4 and later
Information in this document applies to any platform.
SYMPTOMS:
An attempt to insert leap seconds into a timestamp column, fails with:
ORA-01852: seconds must be between 0 and 59
CAUSE
It is not possible to store >59 sec value in a date or timestamp
datatype
SOLUTION
To workaround this issue, the leap second record can be stored in a
varchar2 datatype instead e.g.
SQL> create table test (val number, t varchar2(30));
Table created.
SQL> insert into test values(123, '2012-06-30T23:59:60.000000Z');
1 row created.
Not the best solution, but the only solution.

Related

Charts in Oracle Apex

Hi everyone I wanna ask u about how I can bring data last 24 hours into bar charts, is there any methods to make it please
I have this table without data
datetime
clientchannel
servicename
service_count
13_02_2022 9:35
*****
notification
2
It is a WHERE clause you need, I presume. Something like this:
select ...
from your_table
where datetime >= sysdate - 1;
Why? Because - when you subtract a number from DATE datatype value in Oracle - it subtracts that many days.
SQL> alter session set nls_date_format = 'dd.mm.yyyy hh24:mi:ss';
Session altered.
SQL> select sysdate right_now,
2 sysdate - 1 yesterday
3 from dual;
RIGHT_NOW YESTERDAY
------------------- -------------------
13.02.2022 11:01:34 12.02.2022 11:01:34
SQL>
If you store date values as strings (which means that DATETIME column is declared as e.g. VARCHAR2(20), and that's really bad idea), then you first have to convert it to a valid date datatype value - use TO_DATE function with appropriate format mask:
where to_date(datetime, 'dd_mm_yyyy hh24:mi') >= sysdate - 1
[EDIT] If you want to go 60 minutes back, then subtract that many minutes:
SQL> select sysdate right_now,
2 sysdate - interval '60' minute an_hour_ago
3 from dual;
RIGHT_NOW AN_HOUR_AGO
------------------- -------------------
14.02.2022 07:09:30 14.02.2022 06:09:30
SQL>

Where clause from a subquery

I have a table with business days BUSINESS_DAYS which has all the dates
I have another table with payment information and DUE_DATES
I want to return in my query the next business day IF the DUE_DATE is not a business day
SELECT SQ1.DUE_DATE, SQ2.DATE FROM
(SELECT * FROM
PAYMENTS
ORDER BY
DUE_DATE) SQ1,
(SELECT MIN(DATE) DATE FROM BUSINESS_DAYS WHERE SQ1.DUE_DATE <= DATE GROUP BY DATE) SQ2
Anyone can shed some light?
The way I see it, code you posted doesn't do what you wanted anyway (otherwise, you won't be asking a question at all). Therefore, I'd suggest another approach:
Altering the session (you don't have to do it; my database speaks Croatian so I'm switching to English; also, setting date format to display day name):
SQL> alter session set nls_date_language = 'english';
Session altered.
SQL> alter session set nls_date_format = 'dd.mm.yyyy, dy';
Session altered.
Two CTEs contain
business_days: as commented, only this year's July, weekends excluded, there are no holidays)
payments: two rows, one whose due date is a working day and another whose isn't
Sample data end at line #15, query you might be interested in begins at line #16. Its CASE expression check whether due_date is one of weekend days; if not, due date to be returned is exactly what it is. Otherwise, another SELECT statement returns the first (MIN) business day larger than due_date.
SQL> with
2 business_days (datum) as
3 -- for simplicity, only all dates in this year's July,
4 -- weekends excluded (as they aren't business days), no holidays
5 (select date '2021-07-01' + level - 1
6 from dual
7 where to_char(date '2021-07-01' + level - 1, 'dy')
8 not in ('sat', 'sun')
9 connect by level <= 31
10 ),
11 payments (id, due_date) as
12 (select 1, date '2021-07-14' from dual -- Wednesday, business day
13 union all
14 select 2, date '2021-07-25' from dual -- Sunday, non-business day
15 )
16 select p.id,
17 p.due_date current_due_date,
18 --
19 case when to_char(p.due_date, 'dy') not in ('sat', 'sun') then
20 p.due_date
21 else (select min(b.datum)
22 from business_days b
23 where b.datum > p.due_date
24 )
25 end new_due_date
26 from payments p
27 order by id;
ID CURRENT_DUE_DAT NEW_DUE_DATE
---------- --------------- ---------------
1 14.07.2021, wed 14.07.2021, wed --> Wednesday remains "as is"
2 25.07.2021, sun 26.07.2021, mon --> Sunday switched to Monday
SQL>

Use EPOCH time for timestamp to get records within 1 minute

I was curious to see how in Oracle 12c you can take a timestamp datatype and convert the records into EPOCH time to make them a number and then use that number to find any records within that date column that are within 1 minute of each other (assuming the same day if needed, or simply any calculations within 1 minute).
I tried the following but got an ORA-01873: the leading precision of the interval is too small error.
select (sold_date - to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS'))*86400 as epoch_sold_date from test1;
What is SOLD_DATE? For e.g. SYSDATE (function that returns DATE datatype), your code works OK.
SQL> select (sysdate
2 - to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS')
3 ) * 86400 as epoch_sold_date
4 from dual;
EPOCH_SOLD_DATE
---------------
1600807918
SQL>
As SOLD_DATE is a timestamp, but - it appears that fractions of a second aren't or special interest to you, cast it to DATE:
select (cast (systimestamp as date) --> this
- to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS')
) * 86400 as epoch_sold_date
from dual;
Saying that you get the same result for all rows: well, I don't, and you shouldn't either if SOLD_DATE differs.
SQL> with test (sold_date) as
2 (select timestamp '2020-09-22 00:00:00.000000' from dual union all
3 select timestamp '2015-03-18 00:00:00.000000' from dual
4 )
5 select sold_date,
6 (cast (sold_date as date)
7 - to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS')
8 ) * 86400 as epoch_sold_date
9 from test;
SOLD_DATE EPOCH_SOLD_DATE
------------------------------ ---------------
22.09.20 00:00:00,000000000 1600732800
18.03.15 00:00:00,000000000 1426636800
SQL>
One more edit: when you subtract two timestamps, result is interval day to second. If you extract minutes from it, you get what you wanted:
SQL> with test (sold_date) as
2 (select timestamp '2020-09-22 10:15:00.000000' from dual union all
3 select timestamp '2015-03-18 08:05:00.000000' from dual
4 )
5 select sold_date,
6 lead(sold_date) over (order by sold_date) next_sold_date,
7 --
8 lead(sold_date) over (order by sold_date) - sold_date diff,
9 --
10 extract(day from lead(sold_date) over (order by sold_date) - sold_date) diff_mins
11 from test
12 order by sold_date;
SOLD_DATE NEXT_SOLD_DATE DIFF DIFF_MINS
------------------------------ ------------------------------ ------------------------------ ----------
18.03.15 08:05:00,000000000 22.09.20 10:15:00,000000000 +000002015 02:10:00.000000000 2015
22.09.20 10:15:00,000000000
SQL>
In your case, you'd check whether extracted minutes value is larger than 1 (minute).
If you just want to see how many minutes are there between two timestamps, then
cast them to dates
subtract those dates (and you'll get number of days)
multiply it by 24 (as there are 24 hours in a day) and by 60 (as there are 60 minutes in an hour)
Something like this:
SQL> with test (date_1, date_2) as
2 (select timestamp '2020-09-22 10:15:00.000000',
3 timestamp '2020-09-22 08:05:00.000000' from dual
4 )
5 select (cast(date_1 as date) - cast(date_2 as date)) * 24 * 60 diff_minutes
6 from test;
DIFF_MINUTES
------------
130
SQL>
If you are just looking to compare dates and find rows that are within one minute of each other, you do not need to use epoch time. There are several solutions to this problem on this thread.

checking expiryDate in Oracle query

I have a table which contains the start date, ExpiryDate, I want to write an oracle query which checks if the expiry date is greater than the current system date, Then I want to return that row, else null will be the result of the query.
I wrote something like this,
select Name,Password,StartDate,ExpiryDate from db_name where UserName = 'abc' and status =1 and ExpiryDate >=(SELECT Round((sysdate - to_date('01-JAN-1970','DD-MON-YYYY')) * (86400))*1000 as dt FROM dual);
Here is the table description:
STARTDATE NOT NULL NUMBER(20)
EXPIRYDATE NOT NULL NUMBER(20)
The values:
EXPIRYDATE
----------
1.5880E+12
after performing query like select to_char(startdate),to_char(expirydate) I am getting
TO_CHAR(STARTDATE)
----------------------------------------
TO_CHAR(EXPIRYDATE)
----------------------------------------
1587909960000
1587996480000
But it is working fine for all cases, but if the expiry date is less than( the current time+6hrs) it is giving null, can anyone tell me how to solve this?
Unix epoch time is in the UTC time zone. You can convert the current time to UTC time zone and then subtract the epoch:
SELECT Name,
Password,
StartDate,
ExpiryDate
FROM IM_USER_MANAGEMENT
WHERE UserName = 'abc'
AND status =1
AND ExpiryDate >= ( CAST( SYSTIMESTAMP AT TIME ZONE 'UTC' AS DATE )
- DATE '1970-01-01'
)*24*60*60*1000
Unix epoch time, eh? See if this helps.
Set date format to something recognizable:
SQL> alter session set nls_date_format = 'dd.mm.yyyy hh24:mi:ss';
Session altered.
Sample data:
SQL> select * From test;
STARTDATE EXPIRYDATE
---------------------- ----------------------
1587909960000 1587996480000
Converted to DATE values:
SQL> select
2 date '1970-01-01' + ( 1 / 24 / 60 / 60 / 1000) * startdate startdt,
3 date '1970-01-01' + ( 1 / 24 / 60 / 60 / 1000) * expirydate expdt
4 from test;
STARTDT EXPDT
------------------- -------------------
26.04.2020 14:06:00 27.04.2020 14:08:00
Or, using it along with sysdate:
SQL> select *
2 from test
3 where sysdate between
4 date '1970-01-01' + ( 1 / 24 / 60 / 60 / 1000) * startdate and
5 date '1970-01-01' + ( 1 / 24 / 60 / 60 / 1000) * expirydate;
STARTDATE EXPIRYDATE
---------------------- ----------------------
1587909960000 1587996480000
As sysdate currently is:
SQL> select sysdate from dual;
SYSDATE
-------------------
27.04.2020 12:45:56
It looks to me like these dates of yours are Javascript style timestamps. That is, it looks like they are times since the UNIX epoch 1970-01-01 00:00:00 UTC measured in milliseconds. Notice they're with reference to UTC, not your local time zone. Is your time zone Asia/Dhaka? That's the one six hours ahead of UTC.
It also looks to me like your timestamps have ten-second precision. The two you showed are divisible by 10 000.
This is the formula for converting Javascript times to Oracle UTC date/time values
SELECT TO_DATE('19700101','yyyymmdd') + (1587909960000/86400000) FROM DUAL;
This yields a SYSDATE - style rendering of your values in UTC time, not local time. It yields 2020-04-26 14:06:00
Because you have a six-hour apparent error, I guess your local time zone is Asia/Dhaka, UTC+6. But it also could possibly be America/Denver, UTC-6.
and your time value, run through that formula, yields 2020-04-26 14:06:00. Which seems like a valid recent date/time.
This is a GUESS! If you're working with other peoples' money or lives in your database, ask the person who programmed it. It's not a DBMS-native way of doing things, so you should double-check.
What's going on in the formula?
In Oracle, adding 1.0 to a SYSDATE - style value adds one calendar day to it. So we start with the Oracle date for the UNIX epoch TO_DATE('19700101','yyyymmdd').
Then we take your millisecond timestamp value and convert it to days, dividing by 86 400 000, Finally we add it to the epoch date.
Here are some suggestions about getting the current time in UTC, so you can compare it to your timestamp data. How to get UTC value for SYSDATE on Oracle

How to extract time from a column and subtract from a custom time in Oracle

I would like to compare two time values. The first time value is a custom time which reprsents the start time, for example the column name is Business_Start_time and set to 6:00:00 am. I would also like to extract the time only from a column in Oracle which is a date field that looks like '5/1/2019 12:57:19 PM' and is called 'Completed_Date_Time'. The purpose of this is to compare the businses start date to the time a file was completed. I've tried to convert the 'Completed_Date_Time' field to 'HH24:MI:SS' format which seems to change the datatype to a char(8) value which does not allow me to compare two timestamps.
CAST(TO_CHAR(Completed_Date_Time, 'HH:MI:SS AM') AS CHAR(8))
Convert the values to TIMESTAMP and then you can subtract the values from the values truncated to the start of the day to get an INTERVAL containing the time since midnight and to get the difference you can subtract.
Oracle Setup:
CREATE TABLE table_name ( Business_Start_time, Completed_Date_Time ) AS
SELECT '6:00:00 AM',
TO_DATE( '5/1/2019 12:57:19 PM', 'DD/MM/YYYY HH12:MI:SS AM' )
FROM DUAL
Query:
SELECT ( completed_time - TRUNC( completed_time ) ) -
( start_time - TRUNC( start_time ) ) AS time_difference
FROM (
SELECT TO_TIMESTAMP( business_start_time, 'HH12:MI:SS AM' ) AS start_time,
CAST( Completed_Date_Time AS TIMESTAMP ) AS completed_time
FROM table_name
)
Output:
| TIME_DIFFERENCE |
| :---------------------------- |
| +000000000 06:57:19.000000000 |
db<>fiddle here
Although you wrote both the question and a comment, I'm still not sure what you have and what you want to get. Sample case would help (create table & insert into).
Meanwhile, a few words about it: when subtracting two DATE datatype values, the result is number of days, which means that - if you want to display it in a format which is easier to read & understand - you have to do some calculations (a day has 24 hours; an hour has 60 mintues; and so forth).
Here's an example:
SQL> create table test
2 (business_Start_time date,
3 completed_date_Time date
4 );
Table created.
SQL> insert into test (business_start_time, completed_date_time) values
2 (to_date('05.01.2019 12:57:19', 'dd.mm.yyyy hh24:mi:ss'),
3 to_date('05.01.2019 18:58:20', 'dd.mm.yyyy hh24:mi:ss'));
1 row created.
Simply subtracted, you'd get
SQL> select completed_date_time - business_start_time result from test;
RESULT
----------
,250706019
SQL>
Here's a function which presents such a value in another format, dd:hh:mi (days:hours:minutes) (you can omit days by setting the second parameter to 0):
SQL> create or replace
2 function f_days2ddhhmi (par_broj_dana in number, par_cb_dd in number)
3 return varchar2
4 is
5 /* Converting number of days into dd:hh:mi format
6
7 Date from Date to Diff (days) Retval
8 -------------------- -------------------- -------------- ----------------------------------
9 20.11.2018. 07:00:00 - 20.11.2018. 13:45:00 0,28125 0:06:45 (6 hours 45 minutes)
10 23.10.2018. 07:00:00 - 25.10.2018. 22:12:00 2,63333 2:15:12 (2 daysa 15 hours 12 minutes)
11
12 PAR_BROJ_DANA: 0.28125
13 PAR_CB_DD : display number of days or not? 1 - yes --> 0:06:45
14 0 - no --> 06:45
15 */
16 l_broj_dana number := round (par_broj_dana, 15); -- to avoid 1.99999999999999 days = 1 day 24 hours
17 retval varchar2 (20);
18 begin
19 with podaci
20 as (select trunc (l_broj_dana) broj_dana,
21 round (mod (l_broj_dana * 24, 24), 2) broj_sati
22 from dual)
23 select decode (par_cb_dd,
24 1, lpad (p.broj_dana, 2, '0') || ':',
25 0, null)
26 || lpad (trunc (p.broj_sati), 2, '0')
27 || ':'
28 || lpad (round ( (p.broj_sati - trunc (p.broj_sati)) * 60),
29 2,
30 '0')
31 into retval
32 from podaci p;
33
34 return retval;
35 end f_days2ddhhmi;
36 /
Function created.
Applied to the test table, you'd get
SQL> select f_days2ddhhmi(completed_date_time - business_start_time, 0) result
2 from test;
RESULT
--------------------------------------------------------------------------------
06:01
which means that the difference is 6 hours and 1 minute.
If that's what you asked, see whether you can use it. Feel free to enhance it to seconds etc. if necessary.

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