In one of my SQL queries, I am using
[... and z.READ_TIMESTAMP > TIMESTAMP_TO_EPOCH(TRUNC(SYSDATE-3)]
If I want the date to be exactly 5/31/2017, will I use 'SYSDATE' (date-n) function or some other expression? or how can a modify my query for 5/31/2017
If you want the date to be exactly 5/31/2017 then use TO_DATE() or TO_TIMESTAMP() depending on which data type you need (date or timestamp). As you are using SYSDATE already the the date data type should work.
-- e.g.
select
to_date('5/31/2017','mm/dd/yyyy')
, to_timestamp('5/31/2017','mm/dd/yyyy')
from dual
...
and z.READ_TIMESTAMP > TIMESTAMP_TO_EPOCH(to_date('5/31/2017','mm/dd/yyyy'))
HOWEVER
I suspect you may want more than just a way to establish a fixed date. For example are you asking for "how do I get that last day of the previous month?" which perhaps can be satisfied by using >= and the first day of current month like this:
...
and z.READ_TIMESTAMP >= TIMESTAMP_TO_EPOCH(trunc(sysdate,'MM'))
or if it really is the last day of the previous month can be achieved with a combination of LAST_DAY() and ADD_MONTHS()
and z.READ_TIMESTAMP >
TIMESTAMP_TO_EPOCH( last_day(add_months(trunc(sysdate,'MM'),-1)) )
Without knowing a great deal more about the nature of your data and query purpose please do note that each date you use when "truncated" also has the time set to 00:00:000 - so IF you data contains time within a day other than 00:00:00 then these 2 queries might NOT produce the same result
.... datetimecolumn > to_date('05/31/2017','mm/dd/yyyy') -- "a"
.... datetimecolumn >= to_date('06/01/2017','mm/dd/yyyy') -- "b"
For example "a" the entire 24 hour duration of 05/31/2017 would be included in the results, but for example "b" that same 24 hour duration would be excluded from results. In my experience the last day of any month isn't really the best method for locating date/time based data, instead usually it is the first day of the next month that produces the correct result.
Related
I am running the below query to get data recorded in the past 24 hours. I need the same data recorded starting midnight (DATE > 12:00 AM) and also data recorded starting beginning of the month. Not sure if using between will work or if there is better option. Any suggestions.
SELECT COUNT(NUM)
FROM TABLE
WHERE
STATUS = 'CNLD'
AND
TRUNC(TO_DATE('1970-01-01','YYYY-MM-DD') + OPEN_DATE/86400) = trunc(sysdate)
Output (Just need Count). OPEN_DATE Data Type is NUMBER. the output below displays count in last 24 hours. I need the count beginning midnight and another count starting beginning of the month.
The query you've shown will get the count of rows where OPEN_DATE is an 'epoch date' number representing time after midnight this morning*. The condition:
TRUNC(TO_DATE('1970-01-01','YYYY-MM-DD') + OPEN_DATE/86400) = trunc(sysdate)
requires every OPEN_DATE value in your table (or at least all those for CNLD rows) to be converted from a number to an actual date, which is going to be doing a lot more work than necessary, and would stop a standard index against that column being used. It could be rewritten as:
OPEN_DATE >= (trunc(sysdate) - date '1970-01-01') * 86400
which converts midnight this morning to its epoch equivalent, once, and compares all the numbers against that value; using an index if there is one and the optimiser thinks it's appropriate.
To get everything since the start of the month you could just change the default behaviour of trunc(), which is to truncate to the 'DD' element, to truncate to the start of the month instead:
OPEN_DATE >= (trunc(sysdate, 'MM') - date '1970-01-01') * 86400
And the the last 24 hours, subtract a day from the current time instead of truncating it:
OPEN_DATE >= ((sysdate - 1) - date '1970-01-01') * 86400
db<>fiddle with some made-up data to get 72 back for today, more for the last 24 hours, and more still for the whole month.
Based on your current query I'm assuming there won't be any future-dated values, so you don't need to worry about an upper bound for any of these.
*Ignoring leap seconds...
It sounds like you have a column that is of data type TIMESTAMP and you only want to select rows where that TIMESTAMP indicates that it is today's date? And as a related problem, you want to find those that are the current month, based on some system values like CURRENT TIMESTAMP and CURRENT DATE? If so, let's call your column TRANSACTION_TIMESTAMP instead of (reserved word) DATE. Your first query could be:
SELECT COUNT(NUM)
FROM TABLE
WHERE
STATUS = 'CLND'
AND
DATE(TRANSACTION_TIMESTAMP)=CURRENT DATE
The second example of finding all for the current month up to today's date could be:
SELECT COUNT(NUM)
FROM TABLE
WHERE
STATUS = 'CLND'
AND
YEAR(DATE(TRANSACTION_TIMESTAMP)=YEAR(CURRENT DATE) AND
MONTH(DATE(TRANSACTION_TIMESTAMP)=MONTH(CURRENT DATE) AND
DAY(DATE(TRANSACTION_TIMESTAMP)<=DAY(CURRENT DATE)
Good morning,
I've wrote the following query to get the months difference between a date column (STRT_DT) and a timestamp column (VLD_FRM_TMS) stored in two different tables.
I don't know why it works for some records but does not for others (it calculates one month less)
select ID, floor (months_between (cast(a.VLD_FRM_TMS as date), STRT_DT)) as delta
from TABLE_A a
inner join TABLE_B b
on a.ID = b.ID
This is an example of record for which the calculation does not work:
VLD_FRM_TMS
-----------
28-FEB-21 12.00.00.000000000 AM
STRT_DT
--------
29-OCT-20
The formula calculates 3 months instead of 4...
Could anyone help me in locating the problem?
Thank you in advance
This is exactly the behavior that is described in the documentation:
If date1 and date2 are either the same days of the month or both last days of months, then the result is always an integer. Otherwise Oracle Database calculates the fractional portion of the result based on a 31-day month and considers the difference in time components date1 and date2.
(Note: Highlighting is mine.)
If you run this code:
select months_between(date '2021-02-28', date '2020-10-29') as delta
from dual
The result is 3.9677.
I suspect that you want some other logic. However, the question does not specify what logic you actually do want.
I actually want the months difference regardless of the specific day of the month.
You can truncate both values to the first of the month using the 'MM' format element, and then get the difference between those:
months_between (trunc(a.VLD_FRM_TMS, 'MM'), trunc(STRT_DT, 'MM')) as delta
That will now always be an integer - i.e. a whole number of months - so you don't need to trunc/floor/round the result.
db<>fiddle showing the problem with the old calculation and this version.
I need to round up a month-date based on certain parameters. For example: If I have a parameter where if a day in a given month is between the 6th and the 4th of the next month, I need my query to return the next months date. Is there a way to round up the month given these parameters without hard coding case whens for every single month ever?
SELECT case when date_trunc('day',li.created_at between '2019-03-06 00:00:00' and '2019-04-06 00:00:00' then '2019-04-01' end)
FROM line_items li
If you want the beginning of the month, but offset by 4 days, you can use date_trunc() and subtract some number of days (or add some number of days). You seem to want something like this:
select dateadd(month, 1, date_trunc('month', li.created_at - interval '4 day'))
Another approach is to create a canonical "dates" table that precomputes the mapping from a given date to a new date using your rounding scheme. The mapping could be done outside of redshift in a script and the table loaded in (or within redshift using a user defined function).
I'm currently strugeling to get something done.
I needed only the rows where the date is between a certain date and month.
Example show only the rows where the date is between 01/05 (DD/MM) and 08/07 (DD/MM) the date can be found in the table tasks within the field information.
The year can't make any sense, but the results may only between those two dates in that year.
I've tried:
BETWEEN (TO_DATE ('01/05','DD/MM') AND (TO_DATE('08/07', 'DD/MM')
EXTRACT (DD/MM) from information.
none of those are working for me, I hope that someone of you can help me to figure this out!.
Thanks!
You seem to want to disregard the year. If so, then I would recommend:
TO_CHAR(datecol, 'MM/DD') BETWEEN '05/01' AND '07/08'
In order for BETWEEN to work in this case, you need the format in the order of MM-DD.
If you want this for a particular year, then use direct date comparisons:
datecol >= DATE '2018-05-01' AND
datecol < DATE '2018-07-09' -- note this is one day later
Oracle dates have a time component, so you need to be careful when making comparisons.
I am trying to create a query to that can get some records in a table that is between a from and to date, with the dates being in month/year only. The problem that I am having is trying to get the records when the from and to dates are for the same month/year.
Here is a example of the issue that I am having:
select start_date
from job
where trunc(start_date) between to_date('05-2016','mm-yyyy') and to_date('05-2016','mm-yyyy')
In the job table, there are records with start_date in the month of May, but in order to see them I need to set the to date to '06-2016'. Is there way to get all of the records with a start_date in the month of May by just specifying that the from and to dates is 05-2016?
In your example you are selecting all start_date's between 5/1/2016 and 5/1/2016.
It seems like you want to capture everything in a month, but you are not specifying a format to truncate. Without specifying 'Month' in the Trunc() you are truncating to the day. When you truncate to Month you can now, actually just set it equal to the to_date() rather than between:
select start_date
from job
where trunc(start_date,'Month') = to_date('05-2016','mm-yyyy')
Here is some information on Trunc(date, [fmt]). when the fmt argument is left blank Trunc() defaults to 'round' to the nearest day but there are many other options.
If you want to specify ranges greater than a Month you can use between (but note, this is from the first day of the first to_date() to the first day of the second 'to_date()':
select start_date
from job
where trunc(start_date)
between to_date('06-2016','mm-yyyy')
and to_date('09-2016','mm-yyyy')
In this example all Start_dates would populate between 6/1/2016 and 9/1/2016.
I think the most accurate way to do this would be:
select start_date
from job
where trunc(start_date)
between to_date('06-01-2016','mm-dd-yyyy')
and to_date('09-30-2016','mm-dd-yyyy')
How about?
select start_date
from job
where trunc(start_date, 'mm') between
to_date('05-2016', 'mm-yyyy')
and to_date('05-2016', 'mm-yyyy')
Oracle has no way of interpolating the date on the right end of your between as falling at the end of the month. When to_date() is missing a day value in the format it simply supplies the 1st as the default value. Not sure if that's the behavior your were anticipating.
If instead you truncate dates by month (rather than day) then the comparisons will only involve dates falling on the first of the month. With the dates collapsed that way you can then treat a start and end of the two identical values as an inclusive range. Presumably you'll replace the hard-coded dates with parameters of some form and this works for wider ranges as well. Of course, the between can be just an equality test if you're always querying on a single month. And this isn't going to use an index on your column so it's not necessarily the most efficient.
I think this is what you're looking for. Is there a reason you need to supply the date value(s) in that format? Perhaps there's a better way to approach this using a little date math.
Try like this:
select start_date
from job
where trunc(start_date) between to_date('05-2016','mm-yyyy')
and dateadd('d', -1, dateadd('m', 1, to_date('05-2016','mm-yyyy')))
In order to see an entire month worth of dates, your date range in the between clause must be a full month long.