I have 2 columns in my table both of varchar2. I have a query like
SELECT MYCOLUMN_TIME||' '||MYCOLUMN_TIME_AMPM
FROM MYTABLE
I am getting output 0910 am. I have tried
SELECT TO_CHAR(TO_DATE(MYCOLUMN_TIME,'hh24miss'), 'hh24:mi:ss')||' '||MYCOLUMN_TIME_AMPM
FROM MYTABLE
With this query I am getting Output 09:10:00 pm.
I want Output like 21:10:00 pm. How can we achieve this? Please help.
When using HH24 format mask, 21 hours equals 9 PM. There's no point in having PM along with 21, is there?
When you convert a string (0910) concatenated with am/pm to a date, you use TO_DATE function with appropriate format mask. Date values - in Oracle - contain both date and time component (see datum_1 in the following example). Then apply TO_CHAR to such a result in order to display it as you want (again, by applying desired format mask) - that's datum_2.
For example:
SQL> alter session set nls_date_format = 'dd.mm.yyyy hh:mi pm';
Session altered.
SQL> with mytable (mycolumn_time, mycolumn_time_ampm) as
2 (select '0910', 'am' from dual union all
3 select '1150', 'pm' from dual
4 )
5 select mycolumn_time,
6 mycolumn_time_ampm,
7 to_date(mycolumn_time ||' '||mycolumn_time_ampm, 'hhmi pm') datum_1,
8 --
9 to_char(to_date(mycolumn_time ||' '||mycolumn_time_ampm, 'hhmi pm'), 'hh24:mi') datum_2
10 from mytable;
MYCO MY DATUM_1 DATUM_2
---- -- ------------------- -------
0910 am 01.09.2020 09:10 AM 09:10
1150 pm 01.09.2020 11:50 PM 23:50
SQL>
If you add PM format mask, you'd get
<snip>
9 to_char(to_date(mycolumn_time ||' '||mycolumn_time_ampm, 'hhmi pm'), 'hh24:mi pm') datum_2
10 from mytable; ^^
here
MYCO MY DATUM_1 DATUM_2
---- -- ------------------- --------
0910 am 01.09.2020 09:10 AM 09:10 AM
1150 pm 01.09.2020 11:50 PM 23:50 PM
SQL>
but - as I previously said - it doesn't make sense. There's no e.g. 23:50 AM, but it makes perfect sense in 11:50 AM or 11:50 PM.
Related
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>
I have a schedule of my training, three times a week, for example -
MON, WED,FRI. I need to generate records for my schedule table with dates till the end of the current year when I have training.
The schedule table is:
CREATE TABLE trainingSchedule (
id NUMBER,
training_date DATE
);
If training date already exist - don’t insert a record.
Here's one option. Read comments within code.
SQL> CREATE TABLE trainingSchedule
2 (id NUMBER,
3 training_date DATE
4 );
Table created.
SQL> create sequence seq_tra;
Sequence created.
SQL> -- initial insert (just to show that MERGE will skip it
SQL> insert into trainingschedule values (seq_tra.nextval, date '2021-03-22');
1 row created.
MERGE will skip rows that are already inserted. I understood that you want to insert only dates that follow today's date; if that's not so, just remove the last condition.
SQL> merge into trainingschedule t
2 using (-- this is a calendar for current year
3 select trunc(sysdate, 'yyyy') + level - 1 datum
4 from dual
5 connect by level <= add_months(trunc(sysdate, 'yyyy'), 12) - trunc(sysdate, 'yyyy')
6 ) c
7 on (c.datum = t.training_date)
8 when not matched then insert (id, training_date) values (seq_tra.nextval, c.datum)
9 -- insert only Mondays, Wednesdays and Fridays
10 where to_char(c.datum, 'dy', 'nls_date_language = english') in ('mon', 'wed', 'fri')
11 -- insert only dates that follow today's date ("till the end of the current year")
12 and datum >= trunc(sysdate);
122 rows merged.
SQL>
What's in there?
SQL> select id,
2 to_char(training_date, 'dd.mm.yyyy, dy', 'nls_date_language = english') tr_date
3 from trainingschedule
4 order by training_date;
ID TR_DATE
---------- ------------------------
1 22.03.2021, mon --> see? No duplicates
311 24.03.2021, wed
309 26.03.2021, fri
207 29.03.2021, mon
354 31.03.2021, wed
321 02.04.2021, fri
<skip>
Here is one of our query in the database, i am trying to understand some UTC converstion in our query.
Can some one briefly explain, what the below query is doing?
SELECT
CAST (SYS_EXTRACT_UTC (CAST ( (BEGIN_DATE - (3 / 24)) AS TIMESTAMP)) AS DATE) BEGIN_DATE
FROM offer o
WHERE mask = 'OK'
AFTER CONVERSION OUTPUT : 06-SEP-11 04:00:00
SELECT
BEGIN_DATE
FROM offer o
WHERE mask = 'OK'
BEFORE CONVERSION OUTPUT : 06-SEP-11 00:00:00
SYS_EXTRACT_UTC extracts the UTC (Coordinated Universal Time—formerly Greenwich Mean Time) from a datetime value with time zone offset or time zone region name.
For example,
SQL> SELECT SYS_EXTRACT_UTC(TIMESTAMP '2014-11-05 12:00:00.00 -08:00') as dt
2 FROM DUAL;
DT
---------------------------------------------------------------------------
05-NOV-14 08.00.00.000000000 PM
SQL>
In your case, your timezone is -08:00. So, -3/24 is used.
For example, my timezone is +05:30. The current time is,
SQL> select to_char(sysdate, 'mm/dd/yyyy hh:mi:ss am') dt from dual;
DT
----------------------
11/04/2014 01:12:21 pm
SQL>
The UTC time equivalent is,
SQL> SELECT SYS_EXTRACT_UTC(TIMESTAMP '2014-11-05 01:12:21.00 +05:30') as dt
2 FROM DUAL;
DT
---------------------------------------------------------------------------
04-NOV-14 07.42.21.000000000 PM
SQL>
How are dates stored in Oracle? For example I know most systems use Epoch time to determine what time it is. By calculating how many seconds away from January 1st 1970. Does Oracle do this as well?
The reason I am asking this is I noticed if you take two dates in Oracle and subtract them you get a floating point of how many days are between.
Example
(Sysdate - dateColumn)
would return something like this (depending on the time)
3.32453703703703703703703703703703703704
Now is Oracle doing the conversion and spitting that format out, or does Oracle store dates with how many days it is away from a certain time frame? (Like Epoch time)
There are two types 12 and 13
http://oraclesniplets.tumblr.com/post/1179958393/my-oracle-support-oracle-database-69028-1
Type 13
select dump(sysdate) from dual;
Typ=13 Len=8: 220,7,11,26,16,41,9,0
The format of the date datatype is
Byte 1 - Base 256 year modifier : 220
2 - Base 256 year : 256 * 7 = 1792 + 220 = 2012
3 - Month : 11
4 - Day : 26
5 - Hours : 16
6 - Minutes : 41
7 - Seconds : 09
8 - Unused
2012-11-26 16:41:09
Type 12
select dump(begindate) from tab;
Typ=12 Len=7: 100,112,2,7,1,1,1
The format of the date datatype is
byte 1 - century (excess 100) 100 - 100 = 00
byte 2 - year (excess 100) 112 - 100 = 12
byte 3 - month = 2
byte 4 - day = 7
byte 5 - hour (excess 1) 1 - 1 = 0
byte 6 - minute (excess 1) 1 - 1 = 0
byte 7 - seconds (excess 1) 1 - 1 = 0
0012-02-07 00:00:00
From the manual at http://docs.oracle.com/cd/E11882_01/server.112/e26088/sql_elements001.htm#sthref151
For each DATE value, Oracle stores the following information: year, month, day, hour, minute, and second
So apparently it's not storing an epoch value which is also confirmed by this chapter of the manual:
The database stores dates internally as numbers. Dates are stored in fixed-length fields of 7 bytes each, corresponding to century, year, month, day, hour, minute, and second
How are dates stored in Oracle?
The two data types 12 and 13 are for two different purposes.
Type 12 - Dates stored in table
Type 13 - Date returned by internal date functions like SYSDATE/CURRENT_DATE, also when converting a string literal into date using TO_DATE or ANSI Date literal DATE 'YYYY-MM-DD'.
Test cases:
Basic table setup for type 12:
SQL> CREATE TABLE t(col DATE);
Table created.
SQL> INSERT INTO t SELECT SYSDATE FROM dual;
1 row created.
SQL> COMMIT;
Commit complete.
Check the different cases:
SQL> SELECT DUMP(col) FROM t;
DUMP(COL)
--------------------------------------------------------------------------------
Typ=12 Len=7: 120,116,3,17,18,6,55
SQL> SELECT DUMP(SYSDATE) FROM dual;
DUMP(SYSDATE)
--------------------------------------------------------------------------------
Typ=13 Len=8: 224,7,3,17,17,5,54,0
SQL> SELECT DUMP(CURRENT_DATE) FROM dual;
DUMP(CURRENT_DATE)
--------------------------------------------------------------------------------
Typ=13 Len=8: 224,7,3,17,17,14,20,0
SQL> SELECT DUMP(TO_DATE('17-DEC-1980 12:12:12','DD-MON-YYYY HH24:MI:SS')) FROM dual;
DUMP(TO_DATE('17-DEC-198012:12:12','
------------------------------------
Typ=13 Len=8: 188,7,12,17,12,12,12,0
Using ANSI Date literal, just like TO_DATE:
SQL> SELECT DUMP(DATE '2016-03-17') FROM dual;
DUMP(DATE'2016-03-17')
--------------------------------
Typ=13 Len=8: 224,7,3,17,0,0,0,0
SQL> INSERT INTO t SELECT to_date('17-DEC-1980 12:13:14','DD-MON-YYYY HH24:MI:SS') FROM dual;
1 row created.
SQL> COMMIT;
Commit complete.
SQL> SELECT DUMP(col) FROM t;
DUMP(COL)
--------------------------------------------------------------------------------
Typ=12 Len=7: 120,116,3,17,18,6,55
Typ=12 Len=7: 119,180,12,17,13,14,15
SQL>
As you can see, while storing a date in the table, it uses type 12. The second type 13 is used when converting a string literal into date using date functions or when date returned by internal date functions like SYSDATE/CURRENT_DATE.
In WORK_TIME column in my database table (EMP_WORKS), i have records as below.
WORK_TIME
19:03:00
20:00:00
21:02:00
21:54:00
23:04:00
00:02:00
i want to create a database view using these data. for it i need to get Gap between these times as below.
WORK_TIME GAP
19:03:00 -
20:00:00 00:57:00 (Gap between 19:03:00 and 20:00:00)
21:02:00 01:02:00 (Gap between 20:00:00 and 21:02:00)
21:54:00 00:52:00 (Gap between 21:02:00 and 21:54:00)
23:04:00 01:10:00 (Gap between 21:54:00 and 23:04:00)
00:02:00 00:58:00 (Gap between 23:04:00 and 00:02:00)
How could i do this ?
This query will get you the differences in hours:
SELECT
work_time,
( work_time - LAG(work_time) OVER (ORDER BY work_time) ) * 24 AS gap
FROM emp_works
Example on SQL Fiddle returns this:
WORK_TIME GAP
November, 07 2012 19:03:00+0000 (null)
November, 07 2012 20:00:00+0000 0.95
November, 07 2012 21:02:00+0000 1.033333333333
November, 07 2012 21:54:00+0000 0.866666666667
November, 07 2012 23:04:00+0000 1.166666666667
November, 08 2012 00:02:00+0000 0.966666666667
First you will need to have a primary key in the table containing the DATE/TIME field.
I have set up this demo on SQL Fiddle .. Have a look
I have represented the gap as a factor of hours between the two times. You can manipulate the figure to represent minutes, or days, whatever.
SELECT
TO_CHAR(A.WORK_TIME,'HH24:MI:SS') WORK_FROM,
TO_CHAR(B.WORK_TIME,'HH24:MI:SS') WORK_TO,
ROUND(24*(B.WORK_TIME-A.WORK_TIME),2) GAP FROM
sample A,
SAMPLE B
WHERE A.ID+1 = B.ID(+)
If your primary key values have difference greater than 1 (gaps within the values of the primary key) then you will need to offset the value dynamically like this:
SELECT
TO_CHAR(A.WORK_TIME,'HH24:MI:SS') WORK_FROM,
TO_CHAR(B.WORK_TIME,'HH24:MI:SS') WORK_TO,
ROUND(24*(B.WORK_TIME-A.WORK_TIME),2) GAP FROM
sample A,
SAMPLE B
WHERE b.ID = (select min(C.ID) from sample c where c.id>A.ID)
According to your desired result, provided in the question, you want to see time interval. And also I suppose that the WORK_TIME column is of date datatype and there is a date part(otherwise there will be a negative result of subtraction (previous value of WORK_TIME from 00.02.00)).
SQL> create table Work_times(
2 work_time
3 ) as
4 (
5 select to_date('01.01.2012 19:03:00', 'dd.mm.yyyy hh24:mi:ss') from dual union all
6 select to_date('01.01.2012 20:00:00', 'dd.mm.yyyy hh24:mi:ss') from dual union all
7 select to_date('01.01.2012 21:02:00', 'dd.mm.yyyy hh24:mi:ss') from dual union all
8 select to_date('01.01.2012 21:54:00', 'dd.mm.yyyy hh24:mi:ss') from dual union all
9 select to_date('01.01.2012 23:04:00', 'dd.mm.yyyy hh24:mi:ss') from dual union all
10 select to_date('02.01.2012 00:02:00', 'dd.mm.yyyy hh24:mi:ss') from dual
11 )
12 /
Table created
SQL>
SQL> select to_char(t.work_time, 'hh24.mi.ss') work_time
2 , (t.work_time -
3 lag(t.work_time) over(order by WORK_TIME)) day(1) to second(0) Res
4 from work_times t
5 ;
WORK_TIME RES
--------- -------------------------------------------------------------------------------
19.03.00
20.00.00 +0 00:57:00
21.02.00 +0 01:02:00
21.54.00 +0 00:52:00
23.04.00 +0 01:10:00
00.02.00 +0 00:58:00
6 rows selected