I m using this query to get a result of the difference between the start time and end time of an activity.
SELECT end_time,
NVL(end_time, (TO_Date(sysdate, 'dd/mm/yyyy hh24:mi:ss'))),
(end_time - start_time) * 24 * 60 difference_in_minutes
FROM NCR;
NCR is the name of the table. Start time and end time are in date datatype. Where the end time is NULL, I wanted to put the value as current system date and time. I am getting the results for every row except for the ones where the end time is NULL. Please help and guide
You appear to know the NVL function but you're not using it in your calculation. If you want the NVL to be a part of your calculation, it would need to be part of the calculation
(nvl(end_time,sysdate) - start_time) * 24 * 60 difference_in_minutes
sysdate is already a date so it makes no sense to pass it in to to_date. to_date doesn't take a date parameter, it only takes a string. If you pass a date to to_date, Oracle has to first convert the date to a string using your session's NLS_DATE_FORMAT. Then, to_date runs with whatever format mask you specified. At best, you're just converting it back into the same date you started with. If your session's NLS_DATE_FORMAT doesn't match the format mask you're passing in to to_date, however, you may get a different date back or you may get an error.
Related
I'm trying to convert a char (output from a substr operation) into a dateTime format using TO_DATE with the following format - hh24:mi:ss.
The output of the substr looks fine but as soon as I run it through the TO_DATE function it converts every row for this column into 01-MAR-22.
To demonstrate I have the following:-
SUS_TIME2 shows what I get back from the SUBSTR and it looks fine at this point. SUS_TIME3 then shows what I get back after running it through the TO_DATE function, this where it converts it to 01-MAR-22
,SUBSTR((s.resolve_date-suspend_date),-16,9) sus_time2
,TO_DATE(SUBSTR((s.resolve_date-suspend_date),-16,9), 'hh24:mi:ss') sus_time3
Can anyone see what's going on here please? Thanks
Dates are stored in an internal representation and do not have any intrinsic format. What you are seeing is how your client is choosing to format the actual date value as a string for display, using your session's NLS_DATE_FORMAT setting (not always the case, but this is SQL Developer, so it is here.)
When you call to_date() with only the time components it defaults the date part to the first day of the current month, which is why you are seeing March 1st. That is a bit buried in the documentation:
If you specify a date value without a time component, then the default time is midnight. If you specify a date value without a date, then the default date is the first day of the current month.
But it is setting the time properly on that date, which you can see by either explicitly converting the date back to a string:
to_char(<your date>, 'YYYY-MM-DD HH24:MI:SS')
or by changing your session:
alter session set nls_date_format = 'YYYY-MM-DD HH24:MI:SS'
db<>fiddle
But you should not rely on NLS settings for anything except ad hoc queries; someone else running your code may have different settings. And only convert back to a string at the last moment when you have to display the value in a particular format - store it and pass it around as a native date.
Oracle doesn't have a time-only data type, so if you really only care about the time part then you can use a date (either defaulting to current month, or using an explicit fixed date) and ignore the date part; or potentially use an interval; or use the number of seconds the time represents (i.e. 0-86399). Which is suitable depends on what you'll use the value for.
It looks like you might be substringing the result of subtracting two timestamps; in which case (a) you already have an interval, and (b) you probably need to allow for that difference to span more than one day. You can also extract the individual time components directly from an interval value. So I'd question whether your approach is really appropriate.
You appear to be calculating s.resolve_date-suspend_date which gives you an INTERVAL DAY TO SECOND data type (implying that one or both of s.resolve_date or suspend_date is a TIMESTAMP data type) and then using SUBSTR to extract the time component of the data type and trying to convert that to a date and then display the time component.
Don't do that as using SUBSTR is fragile as it depends on the number of decimal places that the INTERVAL has which, in turn, will depend on the number of fractional seconds that the TIMESTAMP values have.
Just pick a date and add the interval to it and then format it as string to display it:
SELECT s.resolve_date,
suspend_date,
TO_CHAR(
DATE '1900-01-01' + (s.resolve_date-suspend_date),
'hh24:mi:ss'
) sus_time
FROM table_name s
Which, for the sample data:
CREATE TABLE table_name (resolve_date, suspend_date) AS
SELECT CAST(SYSTIMESTAMP AS TIMESTAMP(6)),
CAST(TRUNC(SYSTIMESTAMP) AS TIMESTAMP(6))
FROM DUAL;
Outputs:
RESOLVE_DATE
SUSPEND_DATE
SUS_TIME
2022-03-25 12:59:15.223445
2022-03-25 00:00:00.000000
12:59:15
From your comment:
all i'm trying to do is format the data so that when it's exported to Excel sorting works correctly.
That really is an XY-problem. You can solve it in Excel by either specifying the column format as a time when you import the data into Excel or right-click on the column header and "Format" the column picking the "time" data type with the correct format model.
You can also output the time as a fraction of a day with a numeric data type and then Excel can format it as the correct time using either:
SELECT s.resolve_date,
suspend_date,
MOD(CAST(s.resolve_date AS DATE)-CAST(suspend_date AS DATE), 1) AS sus_time
FROM table_name s;
or
SELECT s.resolve_date,
suspend_date,
TO_CHAR(DATE '1900-01-01' + (s.resolve_date-suspend_date), 'SSSSS')
/ 86400 AS sus_time
FROM table_name s
Which both output:
RESOLVE_DATE
SUSPEND_DATE
SUS_TIME
2022-03-25 13:16:40.204461
2022-03-25 00:00:00.000000
.5532407407407407407407407407407407407407
Which may not be human readable in that format but Excel will reformat it in a time column to 13:16:40.
db<>fiddle here
This is probably an easy question for most of you but how can I get this mask to run based on just the day?
If anyone knows Crystal Reports syntax, we have this and it works {PO_RECEIPTS.DATE_RECEIVED} = currentdate
However, when converting to Oracle SQL, how can I the standard: TO_CHAR
(SYSDATE, 'MM-DD-YYYY HH24:MI:SS') to become range so we can selected everything during the day, not just what matched the second in which the report was ran which it never will.
So something like Today from 00:00:00 to 23:59:59 ?
Thank you!
If PO_RECEIPTS.DATE_RECEIVED is a date column where all the times are set to midnight then you can do:
WHERE PO_RECEIPTS.DATE_RECEIVED = TRUNC(sysdate)
If the values have other times then you can use a range:
WHERE PO_RECEIPTS.DATE_RECEIVED >= TRUNC(sysdate)
AND PO_RECEIPTS.DATE_RECEIVED < TRUNC(sysdate) + 1
Truncating a date sets the time to midnight, by default, so TRUNC(sysdate) is midnight this morning. For the range you get all records equal to or later than midnight this morning, and less than midnight tomorrow - which is what TRUNC(sysdate) + 1 gives you, using normal Oracle datetime arithmetic.
You don't really want to convert it to a string with TO_CHAR(); you'd either have to convert all the column values to strings too (which is inefficient and prevents an index being used), or let the string be (implicitly) converted back to a date anyway. It's better to compare a column value with the same data type to reduce or avoid confusion.
PreparedStatement psnmt=con.prepareStatement("SELECT (?)-(?) as DiffDate FROM dual");
psnmt.setTimestamp(1,ctenderdate);
psnmt.setTimestamp(2,btenderdate);
ResultSet resrt=psnmt.executeQuery();
if(!resrt.next())
{
out.println("No Records Found");
}
else
{
do
{
datediff=resrt.getString("DiffDate");
}
while(resrt.next());
System.out.println("the no of days Difference"+datediff);
}
ctenderdate=2015-06-27 00:00:00.0
btenderdate=2015-06-29 00:00:00.0
datediff=1 10:18:51.940000000
Expected datediff=2
How to round it off datediff to number of days
EDIT
Subtract TIMESTAMP values
If we really want to subtract two TIMESTAMP values, then we have to work with the INTERVAL DAY TO SECOND datatype that's returned. The easiest way to work with that is to use the EXTRACT function.
If want to return integer number of days (emulating the CEIL function) then we could test whether any part of the time (HOUR, MINUTE, SECOND) was non-zero. If they are all zero, we can use just the DAY portion. Otherwise, we have to add 1 to the DAY portion, and return that.
For example:
SELECT EXTRACT(DAY FROM diff.idts)
+ CASE
WHEN EXTRACT(HOUR FROM diff.idts) > 0
OR EXTRACT(MINUTE FROM diff.idts) > 0
OR EXTRACT(SECOND FROM diff.idts) > 0
THEN 1
ELSE 0
END
AS days_diff
FROM ( SELECT ? - ? AS idts FROM dual ) diff
ORIGINAL ANSWER
For Oracle database, you can perform this operation in the database:
SELECT CEIL(TO_DATE(?,'YYYY-MM-DD HH24:MI:SS.F')-TO_DATE(?,'YYYY-MM-DD HH24:MI:SS.F'))
FROM dual
This assumes the bind parameters are passed as strings, in format that matches the format model specified in the TO_DATE function, for example:
'2015-06-27 14:45:21.0'
(I'm assuming Oracle because of the use of the dual table, and because you are using subtraction operation between two dates. You would need a different statement for a different database.)
To unpack that expression a little bit...
The Oracle TO_DATE function converts a character string into an Oracle DATE value. The second argument is the format model, specifies that format of the first argument.
A subtraction operation between two DATE values returns the difference as a number of days (integer days plus fractional days.)
The CEIL function rounds a non-integer value up to the next higher integer.
FOLLOWUP
Q: how to use it with timestamp?
A: A subtraction of two TIMESTAMP values gets returned as an INTERVAL DAY TO SECOND datatype. And I'd prefer to avoid working with that.
In Oracle, when we do a subtraction of two DATE values, we get a decimal number. That's much easier to work with.
And in terms of "rounding" up a difference in days, I'm fine with disregarding fractional seconds.
If I had to pass in TIMESTAMP values, I would convert them to DATE values. The expressions above are already expecting string values, so I would just replace the ? with
TO_CHAR(?,'YYYY-MM-DD HH24:MI:SS')
If I had a requirement to pass in TIMESTAMP datatype, and return integer days difference rounded up, I would use a query like this:
SELECT CEIL( TO_DATE(TO_CHAR( ? ,'YYYY-MM-DD HH24:MI:SS'),'YYYY-MM-DD HH24:MI:SS')
- TO_DATE(TO_CHAR( ? ,'YYYY-MM-DD HH24:MI:SS'),'YYYY-MM-DD HH24:MI:SS')
) AS days_diff
FROM dual
Check out this link. There are answers for results in hours or minutes. What you are looking for should be similar.
My bad. I should not post just-a-link-answers. What you can do, as described there is:
SELECT TRUNC (SYSDATE) - TO_DATE ('10/20/2012', 'mm/dd/yyyy') FROM DUAL;
Notice the following details:
ENDDATE - STARTDATE will give you a number that corresponds to the
number of days between the two dates.
If you want the result in hours, multiply by 24; if minutes, multiply
by 24*60 and so forth.
You can also convert the result to an INTERVAL. There are two type of
intervals: NUMTODSINTERVAL(ENDDATE - STARTDATE, 'DAY') or
NUMTOYMINTERVAL(ENDDATE - STARTDATE, 'DAY')
I have a table with two temporal columns. First (name is DATE) is storing the date (not including the time part) and therefor the datatype is DATE. Second column (name is TIME) is for storing the time in seconds and therefor the datatype is NUMBER.
I need to compare this two dates with a timestamp from another table. How can I calculate the date of the two columns (DATE and TIME) and compare to the timestamp of the other table?
I have tried to calculate the hours out of the time column and add it to the date column, but the output seems not correct:
SELECT to_date(date + (time/3600), 'dd-mm-yy hh24:mi:ss') FROM mytable;
The output is just the date, but not the time component.
You can use the INTERVAL DAY TO SECOND type:
SELECT your_date + NUMTODSINTERVAL(your_time_in_seconds, 'SECOND') FROM dual;
Example:
SELECT TRUNC(SYSDATE) + NUMTODSINTERVAL(39687, 'SECOND') FROM dual;
The calculated date with time is: 10-11-2013 11:01:27
This is a better idea than dividing your value by 3600 in my opinion, as you have an interval in seconds, so it feels natural to use an interval to represent your time, which can then be easily added to a column of DATE datatype.
Oracle Interval in Documentation
NUMTODSINTERVAL Function in documentation
date + (time/3600) is already a DATE, so you don't need to do to_date(). It does have the time part you added though, you just aren't displaying it. If you want to output that as a string in the format you've shown, use to_char() instead:
SELECT to_char(date + (time/3600), 'dd-mm-yy hh24:mi:ss') FROM mytable;
... except that if time is actually in seconds, you need to divide by 86400 (24x60x60), not 3600. At the moment you're relying on your client's default date format, probably NLS_DATE_FORMAT, which doesn't include the time portion from what you've said. That doesn't mean the time isn't there, it just isn't displayed.
But that is just for display. Leave it as a date, by just adding the two values, when comparing against you timestamp, e.g.
WHERE date + (time/86400) < systimestamp
Try like this,
SELECT TO_DATE('11/11/2013','dd/mm/yyyy') + 3600/60/60/24 FROM DUAL;
Your query,
SELECT date + time/60/60/24 FROM mytable;
try using to_timestamp instead of to_date
SELECT LISTING_EOD.LOCATION, LISTING_EOD.APPTTIME, LISTING_EOD.PERSON_ID,
LISTING_EOD.FORENAME, LISTING_EOD.SURNAME, LISTING_EODS.STATUS,
LISTING_EOD.DBDATE
FROM DBNAME.LISTING_EOD LISTING_EOD;
This query returns a list of data processed today, I need to modify to check yesterday's data. I have tried add the below line of code, but it doesn't return anything. Does anyone know how I can achieve this?
where LISTING_EOD.DBDATE = '18-OCT-2012';
If you always want yesterday's data, rather than hard-coding the date you can use:
WHERE LISTING_EOD.DBDATE >= TRUNC(SYSDATE) - 1
AND LISTING_EOD.DBDATE < TRUNC(SYSDATE)
TRUNC(SYSDATE) gives you midnight this morning, so if run today it would give a range between 18-Oct-2010 00:00:00 and 18-Oct-2012 23:59:59.
It's generally not a good idea to use implicit date format masks; your original code assumes your NLS_DATE_FORMAT is set to DD-MON-YYYY, but that might not be correct now (if you're seeing the time in the existing select then it probably isn't), and may well not be in the future. Always use an explicit date format mask, like TO_DATE('18-OCT-2012', 'DD-MON-YYY'), to avoid ambiguity and unexpected behaviour.
If the field is actually VARCHAR2 rather than a DATE - which is bad - then you'll need to convert the date range to a string to get a match:
WHERE LISTING_EOD.DBDATE >= TO_CHAR(TRUNC(SYSDATE) - INTERVAL '1' DAY, 'DD-MON-YYYY HH24:MI:SS')
AND LISTING_EOD.DBDATE <= TO_CHAR(TRUNC(SYSDATE) - INTERVAL '1' SECOND, 'DD-MON-YYYY HH24:MI:SS')
That will work for a single day, just, but you'd have problems looking for a date range. It's much better and safer to store data in a column of the appropriate type.
Dates in Oracle by default contain time as well. If you just specify '18-OCT-2012', it will only match 18-OCT-2012 00:00:00'. One way to get around this is to format your database date to what you are comparing it to, e.g. to_char(LISTING_EOD.DBDATE, 'DD-MON-YYYY') and compare this to '18-OCT-2012'. This comparison will disregard time completely.
If you had a date variable to compare with instead of a string, format this using the same date mask used for the database date. This also gets around any assumptions abut default date format on the database in question.
I realised the 'table' I was querying was a view, examined it inside sqldeveloper, and added '-1' to the sysdate. This query then returned the previous days results.
I successfully retrieved the correct data, thanks for all help received.