I could not find the meaning of the following SQL command:
where date between to_date('2013-03-01', 'yyyy-mm-dd') and trunc(sysdate, 'mm') -1
What does the "-1" mean / does?
The other example is
trunc(months_between(date1, date2))+1
I have searched for this, but could not find a thing.
Thank you for advice!
As others have answered, "date - 1" subtracts one day from the date. Here's more detail on your specific SQL snippets:
where date between to_date('2013-03-01', 'yyyy-mm-dd') and trunc(sysdate, 'mm') -1`
This evaluates to "date between 3/1/2013 and the end of last month"
TRUNC(some date, 'MM') chops the date to the beginning of the month
TRUNC(SYSDATE, 'MM') returns the beginning of the current month
TRUNC(SYSDATE, 'MM')-1 returns the last day of the previous month
trunc(months_between(date1, date2))+1
This is giving the number of full months between date1 and date2, treating any fraction of a month as a whole month. For example, if you gave it the dates 7/28/2013 and 7/29/2013 it would report one month, and it would also report one month if you gave it 7/1/2013 and 7/31/2013.
The MONTHS_BETWEEN function returns, as it implies, the number of months between two dates. The return value will have decimal places - for example a return value of 1.5 means one and a half months.
The TRUNC function, when applied against a numeric, will chop off all its decimals, so TRUNC(1.9999999) will return 1.
+1 is way to add a day to the date
-1 is way to remove a day to the date
In your specific case:
the instruction trunc(sysdate, 'mm') -1 remove one month to the date, in this case is one month before the current date.
the instruction trunc(months_between(date1, date2))+1 compute the difference in month between the two dates and then adds one.
Give a look at this SQLFiddle
it is a lazy way of adding or subtracting day(s)
Related
Would any of you know and would like to share the konwledge how to subtract the number of days from the current date (the data is type = DATE) so that I get the first day of the previous month. Here is an example:
Current Date = '2022-10-27'
The date I want = '2022-09-01'
I know how to get the first day of the current month using this:
(CURRENT_DATE() - EXTRACT(DAY FROM CURRENT_DATE()) +1)
BuT I have no idea how to check how many days there were in the previous month and hence get the correct answer.
I though that maybe DATE_TRUNC(CURRENT_DATE() - EXTRACT(DAY FROM CURRENT_DATE())) would work but I'm getting this error:
"No matching signature for function DATE_TRUNC for argument types: DATE"
SO that's clearly not the way. Any suggestions please? :)
Try using a combination of DATE_TRUNC and DATE_SUB as follows:
select current_date() as curr_date,
date_sub(date_trunc(current_date(), MONTH), INTERVAL 1 MONTH) as lm_day_1
It produces the following:
WHERE to_date(smz_loanservicing.as_of_date) = last_day(add_months(current_date, -1))
The above will provide data only if the loanservicing.as_of_date occurs on the very last day of the month.
Last month (May 31 2020) the last day of the month fell on Sunday.
Is there a way to get the the first day of the month and say if this particular date occurs between the first and last day of the month, show the date? Essentially there were no activities on Sunday so the data was missed.
I tried
to_date(smz_loanservicing.as_of_date)
between first_day(add_month(current_date,-1))
and last_day(add_months(current_date, -1))`
However I get syntax error.
You seem to want to check if your date column belongs to the current month.
The syntax you use would work in Oracle, so let me assume this is the database that you are running. I also assume that column as_of_date is of datatype date (or timestamp).
What you ask for should be as simple as:
where
as_of_date >= trunc(current_date, 'mm')
and as_of_date < add_months(trunc(current_date, 'mm'), 1)
Actually, your syntax would also work in Snowflake - and so would the above code.
Note: if as_of_date actually is a string, then you need to_date() to convert it.
You could just truncate the date to the month, then you don’t need the know the first or last day.
where trunc(as_of_date, ‘MM’) = trunc(current_date, ‘MM’)
I have spent days trying to figure this out to no avail, so hopefully someone can help me. I have a queried date set which contains several fields including a column of dates. What I want to do is create a new field in my query that tells what the Monday and Friday is for the week of that row's particular date.
So for example; if the date in one of my rows is "1/16/18",
the new field should indicate "1/15/18 - 1/19/18".
So basically I need to be able to extract the Monday date (1/15/18) and the Friday date (1/19/18) of the week of 1/16/18 and then concatenate the two with a dash ( - ) in between. I need to do this for every row.
How on earth do I do this? I've been struggling just to figure out how to find the Monday or Friday of the given date...
Assuming that your column is of type date, you can use trunc to get the first day of the week (monday) and then add 4 days to get the friday.
For example:
with yourTable(d) as (select sysdate from dual)
select trunc(d, 'iw'), trunc(d, 'iw') + 4
from yourTable
To format the date as a string in the needed format, you can use to_char; for example:
with yourTable(d) as (select sysdate from dual)
select to_char(trunc(d, 'iw'), 'dd/mm/yy') ||'-'|| to_char(trunc(d, 'iw') + 4, 'dd/mm/yy')
from yourTable
gives
15/01/2018-19/01/18
There may be a simpler, canonical Oracle method to this but you can still reduce it to a simple calculation on your own either way. I'm going to assume you're dealing with only dates falling Monday through Friday. If you do need to deal with weekend dates then you might have to be more explicit about which logical week they should be attached to.
<date> - (to_char(<date>, 'D') - 2) -- Monday
<date> + (6 - to_char(<date>, 'D')) -- Friday
In principle all you need to do is add/subtract the appropriate number of days based on the current day of week (from 1 - 7). There are some implicit casts going on in there and it would probably be wise to handle those better. You might also want to check into NLS settings to make sure you can rely on to_char() using Sunday as the first day of week.
https://docs.oracle.com/cd/B19306_01/server.102/b14200/sql_elements004.htm
You can also use the NEXT_DAY function, as in:
SELECT TRUNC(NEXT_DAY(SYSDATE, 'MON')) - INTERVAL '7' DAY AS PREV_MONDAY,
TRUNC(NEXT_DAY(SYSDATE, 'FRI')) AS NEXT_FRIDAY
FROM DUAL;
Note that using the above, on weekends the Monday will be the Monday preceding the current date, and the Friday will be the Friday following the current date, i.e. there will be 11 days between the two days.
You can also use
SELECT TRUNC(NEXT_DAY(SYSDATE, 'MON')) - INTERVAL '7' DAY AS PREV_MONDAY,
TRUNC(NEXT_DAY(SYSDATE, 'MON')) - INTERVAL '3' DAY AS NEXT_FRIDAY
FROM DUAL;
in which case the Monday and Friday will always be from the same week, but if SYSDATE is on a weekend the Monday and Friday returned will be from the PREVIOUS week.
Alright so I am trying to retrieve data a field we will call DATE_OF_ENTRY and the field is like this.
Example DATE_OF_ENTRY Data
28-NOV-15
So I need to use this field in a script that will be running twice a month to pull certain records. Basically when it's the 16th day of the current month I want all the records from the 1st-15th to be pulled up. When I run this script on the 1st of the next month I want all the records from the 16th-End of last month.
What I am using now
WHERE ROUND(DATE_OF_ENTRY,'MM') = ROUND(sysdate-1,'MM') AND DATE_OF_ENTRY < trunc(sysdate)
The problem with this statement is that it works on the 1st for the 16th to End of the last month, but on the 16th it gets data from the prior month still.
Any help is appreciated!
Using TRUNC() function with MONTH parameter will get the first day of the month.
Using TRUNC() function with DATE_OF_ENTRY will remove the TIME part.
Use + operator to add days to a DATE
SELECT TRUNC(sysdate, 'MONTH') firstDay,
TRUNC(sysdate, 'MONTH') + 15 Day15,
*
FROM yourTable
WHERE TRUNC(DATE_OF_ENTRY) >= TRUNC(sysdate, 'MONTH')
AND TRUNC(DATE_OF_ENTRY) <= TRUNC(sysdate, 'MONTH') + 15
I am comparing two dates in oracle where I stuck at one point in which I have to compare my week with the current week.
Suppose today is 05-Jan-2015 and it's a first week and input date is 29_Dec-2014 and I'm executing below statement to compare:
ld_week BETWEEN FOCUS_WEEK-4 AND FOCUS_WEEK-1
where:
ld_week is the week from input date (last week of current year)
focus_week is week from current date (first week of next year)
hence (52 BETWEEN (1-4) AND (1-1)) always fails.
I am using below function to calculate the week.
FOCUS_WEEK := to_number(to_char(to_date(focus_day),'WW'));
Please let me know how to deal with it.
Your question is a bit vague. I believe you want to try
trunk(date '2014-12-29', 'd')
between
trunk(sysdate - 4*7 , 'd') and
trunk(sysdate - 1*7 , 'd')
With trunc(date, 'd') you obtain the start date of a week.