Checking difference in days only with LAG in Oracle - oracle

I need a bit of help but I'm very close to achieving what I'm looking for thanks to this post. However, it's not exactly the output that I need.
Using LAG to check for differences in dates, I need LAG to ignore differences in time and consider only dates. In other words, it should consider only calendar days, not 24-hour days. Is there any way to achieve that?
Here's what I got so far:
SELECT EMPLOYEE_ID,
SUM(DIFFERENCE) AS DAYS,
DATE_IN,
DATE_OUT
FROM (
SELECT *
FROM (
SELECT EMPLOYEE_ID, DATE_IN, DATE_OUT, ACTIVE,
NVL(DATE_IN - LAG(DATE_IN) OVER (PARTITION BY EMPLOYEE_ID, ACTIVE ORDER BY DATE_IN), 1) AS DIFFERENCE
FROM MY_TABLE
WHERE MY_TABLE.ACTIVE = 1
AND TO_CHAR(DATE_IN, 'YYYY-MM-DD') >= 'user-selected date'
AND TO_CHAR(DATE_OUT, 'YYYY-MM-DD') <= 'other user-selected date'
)
)
GROUP BY EMPLOYEE_ID, DATE_IN, DATE_OUT
ORDER BY DATE_IN
The ouput I get:
EMPLOYEE_ID | DIFFERENCE | DATE_IN | DATE_OUT
000199 1 2013/11/25 08:41:00 2013/11/25 16:41:00
000199 0.970833333333333 2013/11/26 07:59:00 2013/11/26 15:59:00
000199 1 2013/11/27 07:59:00 2013/11/27 15:59:00
000199 1.00069444444444 2013/11/28 08:00:00 2013/11/28 16:00:00
000199 1 2013/11/29 08:00:00 2013/11/29 16:00:00
What I'm looking for:
Differences here should all be 1, time should be ignored. I've tried TO_CHAR(DATE_IN .......) in LAG to get rid of the time part but of course that didn't work :p
Thanks for your help.

For the sake of Googlers:
TRUNC(DATE_IN) - LAG(TRUNC(DATE_IN)
Is the key to ignoring time and getting a result only for days.
Thanks to a_horse_with_no_name for the answer and for teaching me about TRUNC in the process :)

Related

How to generate diff between TIMESTAMP and DATE in SELECT in oracle 10

I need to query 2 tables, one contains a TIMESTAMP(6) column, other contains a DATE column. I want to write a select statement that prints both values and diff between these two in third column.
SB_BATCH.B_CREATE_DT - timestamp
SB_MESSAGE.M_START_TIME - date
SELECT SB_BATCH.B_UID, SB_BATCH.B_CREATE_DT, SB_MESSAGE.M_START_TIME,
to_date(to_char(SB_BATCH.B_CREATE_DT), 'DD-MON-RR HH24:MI:SS') as time_in_minutes
FROM SB_BATCH, SB_MESSAGE
WHERE
SB_BATCH.B_UID = SB_MESSAGE.M_B_UID;
Result:
Error report -
SQL Error: ORA-01830: date format picture ends before converting entire input string
01830. 00000 - "date format picture ends before converting entire input string"
You can subtract two timestamps to get an INTERVAL DAY TO SECOND, from which you calculate how many minutes elapsed between the two timestamps. In order to convert SB_MESSAGE.M_START_TIME to a timestamp you can use CAST.
Note that I have also removed your implicit table join with an explicit INNER JOIN, moving the join condition to the ON clause.
SELECT t.B_UID,
t.B_CREATE_DT,
t.M_START_TIME,
EXTRACT(DAY FROM t.diff)*24*60 +
EXTRACT(HOUR FROM t.diff)*60 +
EXTRACT(MINUTE FROM t.diff) +
ROUND(EXTRACT(SECOND FROM t.diff) / 60.0) AS diff_in_minutes
FROM
(
SELECT SB_BATCH.B_UID,
SB_BATCH.B_CREATE_DT,
SB_MESSAGE.M_START_TIME,
SB_BATCH.B_CREATE_DT - CAST(SB_MESSAGE.M_START_TIME AS TIMESTAMP) AS diff
FROM SB_BATCH
INNER JOIN SB_MESSAGE
ON SB_BATCH.B_UID = SB_MESSAGE.M_B_UID
) t
Convert the timestamp to a date using cast(... as date). Then take the difference between the dates, which is a number - expressed in days, so if you want it in minutes, multiply by 24*60. Then round the result as needed. I made up a small example below to isolate just the steps needed to answer your question. (Note that your query has many other problems, for example you didn't actually take a difference of anything anywhere. If you need help with your query in general, please post it as a separate question.)
select ts, dt, round( (sysdate - cast(ts as date))*24*60, 2) as time_diff_in_minutes
from (select to_timestamp('2016-08-23 03:22:44.734000', 'yyyy-mm-dd hh24:mi:ss.ff') as ts,
sysdate as dt from dual )
;
TS DT TIME_DIFF_IN_MINUTES
-------------------------------- ------------------- --------------------
2016-08-23 03:22:44.734000000 2016-08-23 08:09:15 286.52

MONTHS_BETWEEN Function

Can someone help me understand the working of Oracle Months_Between Function?
If I query select MONTHS_BETWEEN('02-28-2015', '01-28-2015')
I get an integer value of 1 but if I query
select MONTHS_BETWEEN('02-28-2015', '01-29-2015') I get 0.96.
Refer to the documentation. https://docs.oracle.com/cd/B19306_01/server.102/b14200/functions089.htm
Note - the "31 day month" convention may cause weird results around month-ends. Consider:
select months_between(date '2016-07-02', date '2016-07-01') as one_day,
months_between(date '2016-07-01', date '2016-06-30') as another_day
from dual;
ONE_DAY ANOTHER_DAY
---------- -----------
.032258065 .064516129
1 row selected.
As if June had 31 days. It doesn't, but months_between treats it as though it did.
If you're working with just trying to determine the number of months in a set of months and don't care about the days. I find myself in this situation often... You can do a bit of date manipulation which is rather reliable for determining the number of months in a set of months. Say for instance Jul - Sep while starting with dates.
Thusly:
WITH MONTHS AS (
SELECT
SYSDATE DATE_ONE
, SYSDATE+57 DATE_TWO
FROM DUAL
)
SELECT
m.*
,TO_CHAR(m.DATE_ONE,'MON') START_MONTH
,TO_CHAR(m.DATE_TWO,'MON') END_MONTH
,MONTHS_BETWEEN(m.DATE_TWO,m.DATE_ONE) UNEXPECTED_RESULT
,MONTHS_BETWEEN(LAST_DAY(m.DATE_TWO),LAST_DAY(ADD_MONTHS(m.DATE_ONE,-1))) EXPECTED_RESULT
FROM MONTHS m
;

SYSDATE between date in two fields for 6 month period Q

I am trying to set between a date range for 6 months in the past for two different fields that will group the data by month. How do I set such a between clause to achieve this?
SELECT TO_CHAR(mopend, 'MM-yyyy') AS month, MOPSTATUS, COUNT(*) MTS_COMPLETE_CNT
FROM MOPUSER.MOPACTIVITY
WHERE UPPER(MOPSTATUS) = 'COMPLETE'
AND TO_CHAR(MOPACTIVITY.MOPSTART, 'yyyy-mm-dd hh24:mi') BETWEEN TO_CHAR(sysdate,'YYYY-MM-DD')||' 06:02:00' AND TO_CHAR(sysdate,'YYYY-MM-DD')||' 22:59:59'
OR TO_CHAR(MOPACTIVITY.MOPEND, 'yyyy-mm-dd hh24:mi') BETWEEN TO_CHAR(SYSDATE,'YYYY-MM-DD')||' 06:02:00' AND TO_CHAR(SYSDATE,'YYYY-MM-DD')||' 22:59:59'
GROUP BY TO_CHAR(mopend, 'MM-yyyy'), MOPSTATUS
ORDER BY TO_CHAR(mopend, 'MM-yyyy'), MOPSTATUS
I will answer one part of your question first, and then based on your comments, I can give you the full query.
The following query returns the end points between which you want to search. T1 is 06:02 in the morning on the date that is six months back in time. T2 is the last second of today.
select sysdate
,add_months( trunc(sysdate) + interval '06:02' hour to minute, -6) as t1
, trunc(sysdate) + interval '23:59:59' hour to second as t2
from dual;
The above query returns the following (using yyyy-mm-dd hh24:mi:ss):
sydate: 2014-04-11 13:54:28
t1: 2013-10-11 06:02:00
t2: 2014-04-11 23:59:59
If I interpret you correctly, this is the time period you want to search?
For the second part of the answer, I'd need to know the following:
Can any of MOPSTART or MOPEND be null? If so, how do you want to treat those rows?
Do you want to include the end points, i.e. rows where MOPSTART >= t1? Or only where MOTSTART > t1?
Same as (2) but for MOPEND
What month do you want to group by (see below)?
For example, row (a), do you want count it once for each month, or only in JAN (started) or only in JUN(ended)?
JAN FEB MAR APR MAY JUN
a: |-------------------|
b: |---|---|
c: |---|
d: |-----------|
e: |--------|

Adding one month to saved date(oracle)

I have a table A which contains a Date type attribute. I want to write a query to select the date in another table B with value one month after the value in A.Any one know how to do it in oracle?
uhm... This was the first hit on google:
http://psoug.org/reference/date_func.html
It seems you're looking for the "add_months" function.
You need to use the ADD_MONTHS function in Oracle.
http://www.techonthenet.com/oracle/functions/add_months.php
Additional info: If you want to use this function with today's date you can use ADD_MONTHS(SYSDATE, 1) to get one month from now.
The question is to select a date_field from table b where date_field of table b is one month ahead of a date_field in table a.
An additional requirement must be taken into consideration which is currently unspecified in the question. Are we interested in whole months (days of month not taken into consideration) or do we want to include the days which might disqualify dates that are one month ahead but only by a couple of days (example: a=2011-04-30 and b=2011-05-01, b is 1 month ahead but only by 1 day).
In the first case, we must truncate both dates to their year and month values:
SELECT TRUNC( TO_DATE('2011-04-22','yyyy-mm-dd'), 'mm') as trunc_date
FROM dual;
gives:
trunc_date
----------
2011-04-01
In the second case we don't have to modify the dates.
At least two approaches can be used to solve the initial problem:
First one revolves around adding one month to the date_field in table a and finding a row in table b with a matching date.
SELECT b.date_field
FROM tab_a as a
,tab_b as b
WHERE ADD_MONTHS( TRUNC( a.date_field, 'mm' ), 1) = TRUNC( b.date_field, 'mm' )
;
Note the truncated dates. Leaving this out will require a perfect day to day match between dates.
The second approaches is based on calculating the difference in months between two dates and picking a calculation that gives a 1 month difference.
SELECT b.date_field
FROM tab_a as a
,tab_b as b
WHERE months_between( TRUNC( b.date_field, 'mm') , TRUNC(a.date_field, 'mm') ) = 1
The order of the fields in months_between is important here. In the provided example:
for b.date_field one month ahead of a.date_field the value is 1
for b.date_field one month before a.date_field the value is -1 (negative one)
Reversing the order will also reverse the results.
Hope this answers your question.

Oracle: how to add minutes to a timestamp?

I need to add 30 minutes to values in a Oracle date column. I do this in my SELECT statement by specifying
to_char(date_and_time + (.000694 * 31)
which works fine most of the time. But not when the time is on the AM/PM border. For example, adding 30 minutes to 12:30 [which is PM] returns 1:00 which is AM. The answer I expect is 13:00. What's the correct way to do this?
In addition to being able to add a number of days to a date, you can use interval data types assuming you are on Oracle 9i or later, which can be somewhat easier to read,
SQL> ed
Wrote file afiedt.buf
SELECT sysdate, sysdate + interval '30' minute FROM dual
SQL> /
SYSDATE SYSDATE+INTERVAL'30'
-------------------- --------------------
02-NOV-2008 16:21:40 02-NOV-2008 16:51:40
All of the other answers are basically right but I don't think anyone's directly answered your original question.
Assuming that "date_and_time" in your example is a column with type DATE or TIMESTAMP, I think you just need to change this:
to_char(date_and_time + (.000694 * 31))
to this:
to_char(date_and_time + (.000694 * 31), 'DD-MON-YYYY HH24:MI')
It sounds like your default date format uses the "HH" code for the hour, not "HH24".
Also, I think your constant term is both confusing and imprecise. I guess what you did is calculate that (.000694) is about the value of a minute, and you are multiplying it by the number of minutes you want to add (31 in the example, although you said 30 in the text).
I would also start with a day and divide it into the units you want within your code. In this case, (1/48) would be 30 minutes; or if you wanted to break it up for clarity, you could write ( (1/24) * (1/2) ).
This would avoid rounding errors (except for those inherent in floating point which should be meaningless here) and is clearer, at least to me.
UPDATE "TABLE"
SET DATE_FIELD = CURRENT_TIMESTAMP + interval '48' minute
WHERE (...)
Where interval is one of
YEAR
MONTH
DAY
HOUR
MINUTE
SECOND
from http://www.orafaq.com/faq/how_does_one_add_a_day_hour_minute_second_to_a_date_value
The SYSDATE pseudo-column shows the current system date and time. Adding 1 to SYSDATE will advance the date by 1 day. Use fractions to add hours, minutes or seconds to the date
SQL> select sysdate, sysdate+1/24, sysdate +1/1440, sysdate + 1/86400 from dual;
SYSDATE SYSDATE+1/24 SYSDATE+1/1440 SYSDATE+1/86400
-------------------- -------------------- -------------------- --------------------
03-Jul-2002 08:32:12 03-Jul-2002 09:32:12 03-Jul-2002 08:33:12 03-Jul-2002 08:32:13
I prefer using an interval literal for this, because interval '30' minute or interval '5' second is a lot easier to read then 30 / (24 * 60) or 5 / (24 * 60 * 69)
e.g.
some_date + interval '2' hour
some_date + interval '30' minute
some_date + interval '5' second
some_date + interval '2' day
You can also combine several units into one expression:
some_date + interval '2 3:06' day to minute
Adds 2 days, 3 hours and 6 minutes to the date value
The above is also standard SQL and also works in several other DBMS.
More details in the manual: https://docs.oracle.com/database/121/SQLRF/sql_elements003.htm#SQLRF00221
If the data type of the field is date or timestamp, Oracle should always give the correct result if you add the correct number given in number of days (or a the correct fraction of a day in your case). So if you are trying to bump the value in 30 minutes, you should use :
select field + 0.5/24 from table;
Based on the information you provided, I believe this is what you tried to do and I am quite sure it works.
Can we not use this
SELECT date_and_time + INTERVAL '20:00' MINUTE TO SECOND FROM dual;
I am new to this domain.
like that very easily
i added 10 minutes to system date and always in preference use the Db server functions not custom one .
select to_char(sysdate + NUMTODSINTERVAL(10,'MINUTE'),'DD/MM/YYYY HH24:MI:SS') from dual;
Be sure that Oracle understands that the starting time is PM, and to specify the HH24 format mask for the final output.
SELECT to_char((to_date('12:40 PM', 'HH:MI AM') + (1/24/60) * 30), 'HH24:MI') as time
FROM dual
TIME
---------
13:10
Note: the 'AM' in the HH:MI is just the placeholder for the AM/PM meridian indicator. Could be also 'PM'
Oracle now has new built in functions to do this:
select systimestamp START_TIME, systimestamp + NUMTODSINTERVAL(30, 'minute') end_time from dual
Based on what you're asking for, you want the HH24:MI format for to_char.
To edit Date in oracle you can try
select to_char(<columnName> + 5 / 24 + 30 / (24 * 60),
'DD/MM/RRRR hh:mi AM') AS <logicalName> from <tableName>
SELECT to_char(sysdate + (1/24/60) * 30, 'dd/mm/yy HH24:MI am') from dual;
simply you can use this with various date format....

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