For my website I must select all messages sent between midnight (the previous night) and midnight (the next night). Basically, it's a 24 hours range.
I don't know how to do that as I store the date in a timestamp format in my DB.For example, last message was posted on 2013-10-18 11:23:35.
What I want is all message posted between 2013-10-18 00:00:00 and 2013-10-18 23:59:59.
Is that possible, if yes, how could I do that ?
You can calculate the required time in T-SQL as :
-- for previous day mid night as start time
declare #start_datetime datetime,#end_datetime datetime
Select #start_datetime = DATEADD(d,0,DATEDIFF(d,0,GETDATE()))
-- for current day mid night as end time
Select #end_datetime = DATEADD(SS,86399,DATEDIFF(d,0,GETDATE()))
select #start_datetime, #end_datetime
and then use you column name to check whether it exists between these two values.
To find out what happened between DatetimeA and DatetimeB, the sql keyword between is not your friend. It generally causes one to miss records. This construct is better.
where YourDateTimeField >= StartDateTime
and YourDateTimeField < JustAfterTheEndDateTime
In your case, you can simplify it with
where YourDateTimeField >= DateA
and YourDateTimeField < TheDayAfterDateA
Related
i have paramters fields as starttime(=DateAdd("d",-1,now())) and endtime (now()) and status( as dropdown ex:running,succededtec,.) in my report.... when i run the report with the whole timestamp it is working as expected but if i give only date in both the fields without time then am not getting last one days data( for example if starttime is 6/14/2017 and endtime is 6/18/2017 am getting data till 6/17/2017 only) .....one more scenario is when I have no endtime (like status is running we have no endtime) then am getting that.Can anyone help me out.
Thanks
The time defaults to 00:00:00 if not included.
So basically when you're comparing say
06-18-2017 07:52:11 <= 6-18-2017
you're actually comparing
06-18-2017 07:52:11 <= 6-18-2017 00:00:00
Since the time defaults to zero, and you will never get any 6-18 results returned unless they happened at exactly midnight. Set the timestamp in your compare, or use 6-19 as your compare date instead (with the risk of including a random record that happened at exactly midnight on 6-19).
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.
What does this do in a SQL Query? Can someone explain? What does the .5- represent?
WHERE ScheduleEntry.ScheduleDate >= getdate() and ScheduleEntry.ScheduleDate <= getDate() +.50
Think of date unit as 1 day. 0.50 of a day is 1/2 of a day. So this returns anything that has ScheduleDate within half a day from getdate() time forward.
It restricts the rows returned to rows where the ScheduleEntry.ScheduleDate is in the future and where it is not more than .50 units later than the current date. To find out how much time .50 units is equal to, run the following on your console:
SELECT getDate()
SELECT getDate() +.50
The difference between the dates should tell you the difference. Most likely, it is half a day.
GETDATE returns the current date and time in SQL.
You can use addition to "add days" to the current date.
Generally, it is better to use DATE_ADD instead of adding directly and is probably easier to read. Adding 0.5 is akin to adding half a day (or 12 hours).
To better illustrate, the .5 is half a day
SELECT DateDiff(HH,getDate(),getDate() +.50)
Returns 12 hours
In SQL Server, trying to write a age-off report for inventory purposes. Each week, the inventory system marks thousands of rows for deletion. This takes place on Sundays # 06:00:00 as part of weekly SQL DB purge schedule.
Using (yyyy-mm-dd hh:mm:ss:ms) format for closed_time, how can I calculate the numbers of days between that date, until next Sunday of the current week? And to be more elaborate, is there a way to narrow it down to the exact DD:HH:MM? The problem is the each client's Sunday DB schedule for purge varies. So that might be difficult to compute. Might be easier to just calculate whole days until Sunday 00:00:00. I tried using the DATEDIFF function with no success.
SELECT
Yada
DATEDIFF(DAY, closed_time,DW) AS Days_Until_Purged
FROM DB1
WHERE closed_time DESC
Thx in advance
If you choose any Sunday in the past (Such as 06:00 Sunday 2nd January 2000), you can calculate time that has GONE BY since then.
Then, if you take that and do modulo 7-days you get the time that has gone by since the most recent Sunday.
Then, if you do 7 - time_gone_by_since_last_sunday you get the time until the next sunday.
I'm going to do this in minutes to cope with a client that has a setting of 06:30.
DECLARE
#batch_processing_time SMALLDATETIME
SET
#batch_processing_time = '2000-01-02 06:00'
SELECT
(60*24*7) - DATEDIFF(minute, #batch_processing_time, closed_time) % (60*24*7)
FROM
yourTable
That's the number of minutes from each record's closed_time until the next #batch_processing_time.
Divide by (24*60) to get it in days.
try this:
select 8-DATEpart(w, closed_time) AS Days_Until_Purged from DB1 ...
This should solve your problem
SET DATEFIRST 1
Select DATEDIFF(dd,GETDATE(),DATEADD(DAY , 7-DATEPART(WEEKDAY,GETDATE()),GETDATE()))
I have a table described here: http://sqlfiddle.com/#!3/f8852/3
The date_time field for when the time is 00:00 is wrong. For example:
5/24/2013 00:00
This should really be:
5/23/2013 24:00
So hour 00:00 corresponds to the last hour of the previous day (I didn't create this table but have to work with it). Is there way quick way when I do a select I can replace all dates with 00:00 as the time with 24:00 the previous day? I can do it easily in python in a for loop but not quite sure how to structure it in sql. Appreciate the help.
All datetimes are instants in time, not spans of a finite length, and they can exist in only one day. The instant that represents Midnight is by definition, in the next day, the day in which it is the start of the day, i.e., a day is closed on its beginning and open at its end, or, to phrase it again, valid allowable time values within a single calendar date vary from 00:00:00.00000, to 23:59:59.9999.
This would be analogous to asking that the minute value within an hour be allowed to vary from 1 to 60, instead of from 0 to 59, and that the value of 60 was the last minute of the previous hour.
What you are talking about is only a display issue. Even if you could enter a date as 1 Jan 2013 24:00, (24:00:00 is not a legal time of day) it would be entered as a datetime at the start of the date 2 Jan, not at the end of 1 Jan.
One thing that illustrates this, is to notice that, because of rounding (SQL can only resolve datetimes to within about 300 milleseconds), if you create a datetime that is only a few milleseconds before midnight, it will round up to midnight and move to the next day, as can be seen by running the following in enterprise manager...
Select cast ('1 Jan 2013 23:59:59.999' as datetime)
SQL server stoers all datetimes as two integers, one that represents the number days since 1 Jan 1900, and the other the number of ticks (1 tick is 1/300th of a second, about 3.33 ms), since midnight. If it has been zero time interval since Midnight, it is stll the same day, not the previous day.
If you have been inserting data assuming that midnight 00:00:00 means the end of the day, you need to fix that.
If you need to correct your existing data, you need to add one day to every date in your database that has midnight as it's time component, (i.e., has a zero time component).
Update tbale set
date_time = dateAdd(day, 1, date_time)
Where date_time = dateadd(day, datediff(day, 0, date_time), 0)