SQL Server Query - Selecting values BETWEEN 2 Dates - sql-server

I am getting some problems in getting one query done.
I have 2 strings which are suppose to store time in this format (HH:mm Ex: Date1 -> '20:20' and Date2 -> '21:20'). I want to get the current time (CONVERT(VARCHAR(5),getdate(),108) -> to get only 'HH:mm') and get all rows that are between the current date.
The idea is: Select * where "getdate() between date1 and date2", this is not a query, only the idea.
Edit:
Time1 Time2
08:20 09:05
09:05 09:50
10:05 10:50
10:50 11:35
11:45 12:30
12:30 13:15
13:35 14:20
Thx for the solutions, I will check them, but one question how can i "fix" the problem when it's 9:05 (for example), I will get both rows/records, I assume i have to go to the seconds right?

The following constructs two DATETIMEs, based on TIME only, from your input strings (#TimeStr1 and #TimeStr2) then strips the DATE part from GETDATE(). Then you can easily do the query with BETWEEN.
DECLARE
#CurrentTime DATETIME,
#TimeStr1 VARCHAR(12),
#TimeStr2 VARCHAR(12),
#Time1 DATETIME,
#Time2 DATETIME
SET #TimeStr1 = '20:20'
SET #TimeStr2 = '21:20'
SET #Time1 = CAST('1900-01-01 ' + #TimeStr1 AS DATETIME)
SET #Time2 = CAST('1900-01-01 ' + #TimeStr2 AS DATETIME)
-- The following strips the date from datetime leaving only a time
SET #CurrentTime = DateAdd(ss, DateDiff(ss, DateAdd(dd, DateDiff(dd, 0, GetDate()), 0), GetDate()), 0)
SELECT * FROM YourTable WHERE #CurrentTime BETWEEN #Time1 AND #Time2
This will work for all versions of SQL SERVER. If you are using a version >= 2008 then a simpler version of the above exists.
If you are worried about overlaps (eg your "09:05" problem) use the following query that avoids the problem by using > and <= rather then BETWEEN
SELECT * FROM YourTable WHERE #CurrentTime > #Time1 AND #CurrentTime <= #Time2

Related

SQL Date-Time Conversion with nested converts experiences random conversion errors

Looking for assistance with a strange issue if anyone has ideas:
I have a SQL that statement works most of the time in a T-SQL script but crashes occasionally. I have identified the data that a crash occurs on and cannot identify any difference between data rows that work.
The goal of this code is to add the time to an already existing datetime value that has 00:00:00 as the time from the second time column (as outlined below). My goal is to combine both columns into YYYY-MM-DD HH:MM:SS format, but I had to convert them to char first to trim off the orignal 00:00:00.
Columns
LogDate - contains date only in DateTime format (YYYY-MM-DD HH:MM:SS)
LogTime - contains the time of the action and is in varchar format (HH:MM)
SQL Conversion
SELECT CONVERT(DATETIME, CONVERT(CHAR(8), LogDate, 112) + ' ' + CONVERT(CHAR(8), LogTime, 108))
FROM TestTable
WHERE EventSerial = '100001'
However, if I change the EventSerial in the above statement to a different row, such as '100002', the statement works.
The data for each row is below:
EventSerial 100001's values:
LogDate: 2015-04-02 00:00:00.000
LogTime: 10:04
EventSerial 100002's values:
LogDate: 2015-04-02 00:00:00.000
LogTime: 10:48
Running with data set 1 fails, running with data set 2 produces output. Also, running the code without the final datetime conversion works, or if I run the code with the string manually it works (as outlined below:)
SELECT CONVERT(CHAR(8), LogDate, 112) + ' ' + CONVERT(CHAR(8), LogTime, 108)
FROM TestTable
WHERE EventSerial = '100001'
SELECT CONVERT(DATETIME, '20150402 10:48')
SELECT CONVERT(DATETIME, '20150402 10:04')
Any suggestions, I'm sure its something silly that I'm missing (and I probably took the long way around the issue anyway. The desired output would be 2015-04-02 10:04:00
First, datetime has no format. (why?)
Second, you don't need to convert the datetime value to char to add hours and minutes, just use DateAdd:
SELECT DATEADD(Minute,
CAST(RIGHT(LogTime, 2) as int),
DATEADD(Hour,
CAST(LEFT(LogTime, 2) as int),
LogDate
)
)
FROM TestTable
WHERE EventSerial = '100001'
Also, note that convert does not hold a style for yyyymmdd hh:mm
Note: code was written directly here, there might be some mistakes.
I'm not sure why you're getting the error... possibly there are some unseen characters in your varchar time field... like a tab or something maybe? Try this query:
SELECT ascii(substring(LogTime,1,1)) Char1,
ascii(substring(LogTime,2,1)) Char2,
ascii(substring(LogTime,3,1)) Char3,
ascii(substring(LogTime,4,1)) Char4,
ascii(substring(LogTime,5,1)) Char5
FROM TestTable
WHERE EventSerial = '100001'
It should show these results:
Char1 Char2 Char3 Char4 Char5
----------- ----------- ----------- ----------- -----------
49 48 58 48 52
(1 row(s) affected)
This would be a bit more efficient:
select dateadd(minute, datediff(minute,0, LogTime), LogDate)
FROM TestTable
But this assumes that your date field always has 00:00:00 time information. If you want to be sure that is stripped out as well you could use:
select dateadd(minute, datediff(minute,0, LogTime), dateadd(day, datediff(day, 0, Logdate),0))
FROM TestTable

SQL query not returning all rows

I have a table in SQL Server which has many rows, with a created_date column. This column has rows starting from the year 2006.
I want to get all the rows which were created in and before February, 2015. This stored procedure has a parameter #month. It should select all the rows based on the #month value entered.
Here is my query:
select *
from products
where 1=1
and year(created_date) <= 2015
and month(created_date) <= #month
But this query returns only the records which were created in and before February month of previous years excluding records which were created in other months of 2014 (e.g., 2014-03-17, 2014-05-05 are excluded).
I have to get a new date based on the #month entered. Suppose I entered month July, I want to have condition "where created_date < 2015-07-31". So I can do something like this,
So I have changed my query,
declare #date datetime
set #date = CAST((2015 + '-' + #month + '-' + 28) as datetime)
select *
from products
where 1=1
and year(created_date) <= 2015
But this query returns 1905-08-08 00:00:00.000 and I want to get 2015-02-28 00:00:00.000 and also I have to find total number of days based on the #month entered so that I can pass that number to CAST((2015 + '-' + #month + '-' + 28) as datetime) instead of 28.
Just use a single date and specify that the created_date column must be less than that date:
declare #newestDate datetime = '2015-03-01'
select *
from products
where created_date < #newestDate
Note that I set the date to be the 1st March but in the query I use < rather than <=. This will cope with a created_date value including a time component, e.g. 2015-02-28 23:59:59
To generate the value of "February of previous year", you may actually be wanting to use the current month of last year, if so, your date would be:
declare #newestDate datetime =
DATEADD(year, -1, DATEADD(month, DATEDIFF(month, 0, GETDATE())+1, 0))
This would then work next month (i.e. March) and would give your query a rolling month.
Always compare date/time fields to a single value where possible -- this is best for performance as well. You can "round" dates with DATEADD and DATEDIFF.
DECLARE #startOfNextMonth DATETIME;
SELECT #startOfNextMonth = DATEADD(MONTH, DATEDIFF(MONTH, 0, GETDATE()) + 1, 0);
select * from products where 1=1 and created_date < #startOfNextMonth;
String manipulation to convert dates is also possible, but tends to perform worse and is tricky to get right. This technique applies in general if you want to "round" to years, minutes, 15-second periods, etcetera, which is much harder with strings.
If you can, rewrite your stored procedure to not take a #month parameter but an absolute value that your clients calculate -- it's more general and tends to be easier to work with. Your query then simply reduces to
select * from products where 1=1 and created_date < #limit;
Of course, if you must use a #month, you can construct this offset in the stored procedure itself:
DECLARE #limit DATETIME =
DATEFROMPARTS(DATEPART(YEAR, GETDATE()), #month, 1)
;
This takes advantage of DATEFROMPARTS, which was introduced with SQL Server 2012. For previous versions, reliably constructing a date is considerably messier. There are many wrong ways to do it that will break if the regional settings are set to something unexpected. DATEADD is again of assistance:
DECLARE #limit DATETIME =
DATEADD(MONTH, (DATEPART(YEAR, GETDATE()) - 1900) * 12 + #month - 1, 0)
;
These are not the only methods to construct datetime values, but string manipulation is in any case tricky (because the only reliable format that will not break under regional settings is YYYYMMDD, no dashes).
In this question: Create a date with T-SQL you will see how to construct an sql-server date data type given a certain year and month. Suppose you call that 'my_date'.
You will then be able to do the following:
SELECT * FROM products WHERE created_date < my_date

Getting plot data from date-range efficiently

I'm trying to create utilization graph for a telephone system. I have sets of data which is in the table format
ID *
StartDate
EndDate
From
To
What I'm trying to do is get SQL to to output me a list of plot points every 5 minutes, so basically
The count of active calls (between StartDate and EndDate) for every 5 minutes in a day.
The result beign something like
Date Time Count
2000-01-01 00:00:00 10
2000-01-01 00:05:00 2
2000-01-01 00:10:00 7
Can anyone suggest a way to generate said data? I'm at a loss here! The stuff I've been thinking abut all involves a creating a big loop and running a query for every 5 seconds which seems super inefficient.
The method I was originally thinking was :-
storedProc GetSamples(SampleStartDate, SampleEndDate)
Create memory table for result data
for every 5mins as sample between SampleStartDate and SampleEndDate
SELECT #SampleCount = COUNT(1) FROM Samples where 5mins BETWEEN StartDate AND EndDate
UPDATE memoryTable SET count=#SampleCount WHERE time = 5mins
end
end
If you have a recent enough version of SQL Server (2008+), you ought to be able to do this with a CTE joined to your phone call log, like this (CTE base found here):
DECLARE #StartDate DATETIME
DECLARE #EndDate DATETIME
SET #StartDate = '2000-01-01 00:00:00.000'
SET #EndDate = '2000-01-02 00:00:00.000'
;WITH DateSequence( [PlotPointDate] ) AS
(
SELECT #StartDate AS [PlotPointDate]
UNION ALL
SELECT DATEADD(MINUTE, 5, [PlotPointDate] )
FROM DateSequence
WHERE [PlotPointDate] < #EndDate
)
--select result
SELECT
PlotPointDate, COUNT(YourTable.ID) AS TotalActiveCalls
FROM
DateSequence
LEFT JOIN
YourTable ON
YourTable.StartDate <= DateSequence.PlotPointDate AND
(YourTable.EndDate >= DateSequence.PlotPointDate OR YourTable.EndDate IS NULL)
GROUP BY PlotPointDate
OPTION (MaxRecursion 10000)

DATEADD with part days

I'm having a little trouble getting a count of dates in SQL SERVER. I require the number of calender days between 2 dates start and ends dates included. The problem with the example below is that it always returns 10 when I believe it should be 11.
DECLARE #FROM DATETIME, #TO DATETIME
SET #FROM = '18/12/2011 00:00:00'
SET #TO = '28/12/2011 00:00:00'
SELECT
DATEDIFF(MINUTE,#FROM,#TO), -- Returns 14459
DATEDIFF(HOUR,#FROM,#TO), -- Returns 241
DATEDIFF(DAY,#FROM,#TO), -- Returns 10
CEILING(CAST((DATEDIFF(HOUR,#FROM,#TO) / 24) as DECIMAL(9,5))) --Returns 10
CEILING(CAST(CEILING(CEILING(CAST(DATEDIFF(SECOND,#FROM,#TO) as DECIMAL(18,5))) / 60) / 60 as DECIMAL(9,5)) / 24) --Returns 10
The bottom line works if there is at least 1 second between the times but I must account for all scenarios.
My only other thought was to simply add one to the date diff to account for the part days? Is that reliable?
DATEDIFF(DAY,#FROM,#TO) + 1
I came across when answering this question How to find the total between the dates for each values
Is an expression that can be resolved to a time, date, smalldatetime,
datetime, datetime2, or datetimeoffset value. date can be an
expression, column expression, user-defined variable or string
literal. startdate is subtracted from end date.
This is taken from MSDN here.
28-18 = 10. I think you will always have to add 1 in the scenario you have because of the definition for DATEDIFF.
You need to set the #TO date to:
SET #TO = '28/12/2011 23:59:59'
To get the number of days between two dates (ignoring the time of day), including the start and end date, try;
SELECT FLOOR(CONVERT(FLOAT, #TO))-FLOOR(CONVERT(FLOAT, #FROM))+1
Edit:
SELECT DATEDIFF(d, #FROM, #TO)+1
seems to return the exact same results, which would indeed make it a more elegant way of doing it. Always thought DATEDIFF timeparts were about truncating after the calculation (which would give the wrong result if the start time was later in the day than the end time) and not truncating before the calculation which gives the correct result for your case. You learn something new every day :)
If you want a close equivalent of the C# DateTime.TotalDays() function (i.e. to know fractional days) you can use the following:
DECLARE #start DATETIME = '10 Apr 2012 15:00'
DECLARE #end DATETIME = '12 Apr 2012 16:00'
SELECT CONVERT(FLOAT, DATEDIFF(SECOND, #start, #end)) / 86400
*Note: 86400 = seconds in a day = 24 hours x 60 mins x 60 seconds

SQL Server remove milliseconds from datetime

select *
from table
where date > '2010-07-20 03:21:52'
which I would expect to not give me any results... EXCEPT I'm getting a record with a datetime of 2010-07-20 03:21:52.577
how can I make the query ignore milliseconds?
You just have to figure out the millisecond part of the date and subtract it out before comparison, like this:
select *
from table
where DATEADD(ms, -DATEPART(ms, date), date) > '2010-07-20 03:21:52'
If you are using SQL Server (starting with 2008), choose one of this:
CONVERT(DATETIME2(0), YourDateField)
LEFT(RTRIM(CONVERT(DATETIMEOFFSET, YourDateField)), 19)
CONVERT(DATETIMEOFFSET(0), YourDateField) -- with the addition of a time zone offset
Try:
SELECT *
FROM table
WHERE datetime >
CONVERT(DATETIME,
CONVERT(VARCHAR(20),
CONVERT(DATETIME, '2010-07-20 03:21:52'), 120))
Or if your date is an actual datetime value:
DECLARE #date DATETIME
SET #date = GETDATE()
SELECT CONVERT(DATETIME, CONVERT(VARCHAR(20), #date, 120))
The conversion to style 120 cuts off the milliseconds...
select * from table
where DATEADD(ms, DATEDIFF(ms, '20000101', date), '20000101') > '2010-07-20 03:21:52'
You'll have to trim milliseconds before comparison, which will be slow over many rows
Do one of these to fix this:
created a computed column with the expressions above to compare against
remove milliseconds on insert/update to avoid the read overhead
If SQL Server 2008, use datetime2(0)
Use CAST with following parameters:
Date
select Cast('2017-10-11 14:38:50.540' as date)
Output: 2017-10-11
Datetime
select Cast('2017-10-11 14:38:50.540' as datetime)
Output: 2017-10-11 14:38:50.540
SmallDatetime
select Cast('2017-10-11 14:38:50.540' as smalldatetime)
Output: 2017-10-11 14:39:00
Note this method rounds to whole minutes (so you lose the seconds as well as the milliseconds)
DatetimeOffset
select Cast('2017-10-11 14:38:50.540' as datetimeoffset)
Output: 2017-10-11 14:38:50.5400000 +00:00
Datetime2
select Cast('2017-10-11 14:38:50.540' as datetime2)
Output: 2017-10-11 14:38:50.5400000
For this particular query, why make expensive function calls for each row when you could just ask for values starting at the next higher second:
select *
from table
where date >= '2010-07-20 03:21:53'
Use 'Smalldatetime' data type
select convert(smalldatetime, getdate())
will fetch
2015-01-08 15:27:00
There's more than one way to do it:
select 1 where datediff(second, '2010-07-20 03:21:52', '2010-07-20 03:21:52.577') >= 0
or
select *
from table
where datediff(second, '2010-07-20 03:21:52', date) >= 0
one less function call, but you have to be beware of overflowing the max integer if the dates are too far apart.
One more way I've set up SQL Server queries to ignore milliseconds when I'm looking for events from a particular second (in a parameter in "YYYY-MM-DD HH:TT:SS" format) using a stored procedure:
WHERE
...[Time_stamp] >= CAST(CONCAT(#YYYYMMDDHHTTSS,'.000') as DateTime) AND
...[Time_stamp] <= CAST(CONCAT(#YYYYMMDDHHTTSS,'.999') as DateTime)
You could use something similar to ignore minutes and seconds too.
Please try this
select substring('12:20:19.8470000',1,(CHARINDEX('.','12:20:19.8470000',1)-1))
(No column name)
12:20:19
I'm very late but I had the same issue a few days ago. None of the solutions above worked or seemed fit. I just needed a timestamp without milliseconds so I converted to a string using Date_Format and then back to a date with Str_To_Date:
STR_TO_DATE(DATE_FORMAT(your-timestamp-here, '%Y-%m-%d %H:%i:%s'),'%Y-%m-%d %H:%i:%s')
Its a little messy but works like a charm.
May be this will help..
SELECT [Datetime] = CAST('20120228' AS smalldatetime)
o/p:
2012-02-28 00:00:00
Review this example:
declare #now datetimeoffset = sysdatetimeoffset();
select #now;
-- 1
select convert(datetimeoffset(0), #now, 120);
-- 2
select convert(datetimeoffset, convert(varchar, #now, 120));
which yields output like the following:
2021-07-30 09:21:37.7000000 +00:00
-- 1
2021-07-30 09:21:38 +00:00
-- 2
2021-07-30 09:21:37.0000000 +00:00
Note that for (1), the result is rounded (up in this case), while for (2) it is truncated.
Therefore, if you want to truncate the milliseconds off a date(time)-type value as per the question, you must use:
declare #myDateTimeValue = <date-time-value>
select cast(convert(varchar, #myDateValue, 120) as <same-type-as-#myDateTimeValue>);

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