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I am trying to subtract one column from another column, and then sum the result. However, whatever I change I keep getting one of the two errors as mentioned in the title.
From all other questions posted, I derived that my statement should be something like:
SELECT SUM(EndTime-BeginTime) AS TotalTime FROM TimeRegister
WHERE OrderNumber = 00000 AND Activity = 11111;
As per suggestion in another topic, I changed the statement to:
SELECT SUM(CONVERT(varchar(EndTime-BeginTime), 108)) AS TotalTime FROM TimeRegister
WHERE OrderNumber = 00000 AND Activity = 11111;
However, I still receive the error.
The times are stored as follows:
1-1-1900 7:30:00
Thanks for any suggestion...
Edit 1: Oh, I am using a Microsoft Query through ODBC for SQL in Excel, kind of like:
Excel vlookup incorporating SQL table
Edit 2: I prefer to have the output again in the HH:MM format.
The thing is, when I copy the complete database to excel, everything works just fine. I can subtract the columns and sum up. I just dont want to that manually every day....
I just checked the SQL database, and the column is of Date/Time type.
First of all, trying to solve date or numeric issues by converting to text never solves anything, it adds additional problems like failed conversions or unexpected results.
SQL Server doesn't have a time interval type. If you subtract two datetime values you get back another datetime value that represents the difference as the offset since 1900-01-01. The following query :
select getdate() - dateadd(d,-1,getdate())
Will return :
1900-01-02 00:00:00.000
Which is 1 full day after 1900-01-01.
datetime values can't be summed though. SQL Server does have a time type but that just represents the time of day. Even if today - yesterday worked, converting that to time would return 00:00.
A quick solution is to use DATEDIFF to calculate the difference between two dates in whatever unit is required - hourss, minutes, seconds etc. Be aware though that DATEDIFF returns the number of interval boundaries crossed. DATEDIFF(DAY,...) between 11pm yesterday and 1am today will return 1, because 1 day boundary was crossed.
You can use
SELECT sum(datediff(minute,EndTime,BeginTime)) AS TotalMinutes
FROM TimeRegister
WHERE OrderNumber = 00000 AND Activity = 11111;
To calculate the difference in minutes and format it as a time interval on the client.
Another option is to cast the datetime to a float before summing, then back to datetime:
SELECT cast( sum(cast(EndTime - BeginTime as datetime)) as datetime) AS TotalOffset
FROM TimeRegister
WHERE OrderNumber = 00000 AND Activity = 11111;
A 2-day duration would appear as :
1900-01-03 00:00:00.000
This works because datetime can be cast to a float whose integral part represents the offset from 1900-01-01 and the fractional part the time.
A client written in a language like C# that does support intervals could subtract 1900-01-01 from this to get back the actual duration, eg :
TimeSpan duration = sumResult - new DateTime(1900,1,1);
Another option would be to avoid the final cast and just use the resulting float value as the number of days.
Displaying in Excel
The last option could be the easiest way to display the duration in Excel! Excel dates are actually stored as floats. What makes them appear as dates or times is the cell's formatting.
You can set a cells format to [h]:mm:ss to display any number as a duration. The [] is important - without it Excel will only display the time part of the "date".
If you enter 2 in a cell, h:mm:ss will show it as 0:00:00 while [h]:mm:ss will display 48:00:00, 48 hours.
Despite its strangeness,
SELECT sum(cast(EndTime - BeginTime as datetime)) AS TotalDuration
FROM TimeRegister
WHERE OrderNumber = 00000 AND Activity = 11111;
May be the best option to display a duration sum in Excel
You seem to want datediff():
SELECT SUM(DATEDIFF(second, BeginTime, EndTime) AS TotalTime
FROM TimeRegister
WHERE OrderNumber = 00000 AND Activity = 11111;
How about the following:
WITH totalTime AS (
SELECT SUM(DATEDIFF(second, EndTime, BeginTime)) as TimeInSecond
FROM TimeRegister
WHERE OrderNumber = 00000 AND Activity = 11111;
)
SELECT RIGHT('0' + CAST(TimeinSecond / 3600 AS VARCHAR),2) + ':' +
RIGHT('0' + CAST((TimeinSecond / 60) % 60 AS VARCHAR),2) + ':' +
RIGHT('0' + CAST(TimeinSecond % 60 AS VARCHAR),2) AS TimeElapsed
FROM totalTime;
In this solution, the time is converted into seconds, before being totalled, and then converted to HH:MM:SS.
I am working on a project in which dates and times ar stored as a varchar e.g. "30-11-2017,7:30" first date in dd-mm-yyy format and then time separated with a comma. I am trying to filter on it but it is not working correctly kindly guide me how to filter data on date.
select *
from timetrack
where startDateAndTime >= '30-11-2017,7:30'
In attached image records have been shown. When I apply above query it shows no records
You can easily convert your date to SQL datatype datetime uisng parse function, for example select parse('30-11-2017,7:30' as datetime using 'it-IT').
So, in your case, you can apply this function in where clause, so you can easily apply comparison between dates:
select *
from timetrack
where parse(startDateAndTime as datetime using 'it-IT') >= '2017-11-30 07:30:00.000'
Your format is apparently italian :) But you have to specify your own date in the format convertable to datetime, as I have done in above example.
NOTE: parse is available starting with SQL Management Studio 2012.
Unless you are using ISO date format (yyyy-MM-dd HH:mm:ss or close) applying ordering (which inequalities like greater than or equal use) will not work: the date order is disconnected from the string ordering.
You'll need to parse the date and times into a real date time type and then compare to that (details of this depend on which RDBMS you are using).
If, you want to just filter out the date then you could use convert() function for SQL Server
select *
from timetrack
where startDateAndTime >= convert(date, left(#date, 10), 103)
Else convert it to datetime as follow
select *
from timetrack
where startDateAndTime >= convert(datetime, left(#date, 10)+' ' +
reverse(left(reverse(#date), charindex(',', reverse(#date))-1)), 103)
You need the date in a datetime column, Otherwise you can't filter with your current varchar format of your date.
Without changing the existing columns, this can be achieved by making a computed column and making it persisted to optimize performance.
ALTER TABLE test add CstartDateTime
as convert(datetime, substring(startDateAndTime, 7,4)+ substring(startDateAndTime, 4,2)
+ left(startDateAndTime, 2) +' '+ right(startDateAndTime, 5), 112) persisted
Note: this require all rows in the column contains a valid date with the current format
Firstly, you need to check what is the data that is entered in the 'startDateAndTime' column,then you can convert that varchar into date format
If the data in 'startDateAndTime' column has data like '30-11-2017,07:30', you would then have to convert it into date:
SELECT to_date('30-11-2017,07:30','dd-mm-yyyy,hh:mm') from dual; --check this
--Your query:
SELECT to_date(startDateAndTime ,'dd-mm-yyyy,hh:mm') from timetrack;
I have date formats that are as follows:
Date_str
19-12-2007
31-7-2009
3-1-2010
31-11-2009
etc.
I can't do the following:
CONCAT(RIGHT(Date_str,4),SUBSTRING(Date_str,3,3),LEFT(2))
because as you can see above, the dates are not the same length. Is there a way in SQL Server to extract the date as datetime/date?
I also tried
Convert(datetime, Date_str)
but it just threw an error:
The conversion of a varchar data type to a datetime data type resulted
in an out-of-range value.
If 2012+, I would use Try_Convert(). This will return bogus dates as NULL.
Example
Declare #YourTable Table ([Date_str] varchar(50))
Insert Into #YourTable Values
('19-12-2007')
,('31-7-2009')
,('3-1-2010')
,('31-11-2009')
Select *
,try_convert(date,Date_Str,105)
from #YourTable
Returns
Date_str (No column name)
19-12-2007 2007-12-19
31-7-2009 2009-07-31
3-1-2010 2010-01-03
31-11-2009 NULL -- Notice 11/31 is NOT a date
See https://learn.microsoft.com/en-us/sql/t-sql/functions/cast-and-convert-transact-sql for date formats
You probably need
CONVERT(DateTime, Date_str, 105)
As I mentioned in the comments, the only realistic solution is to convert that string into a proper date-typed column. The current format doesn't allow date sorting, or search for a range of dates, eg to find entries in the last week, or between one date and the other.
Parsing with CONVERT or TRY_PARSE means that no indexes can be used to speed up queries. Each time :
WHERE CONVERT(Date, Date_str, 105) > '20170101'
is used, the server will have to scan the entire table to convert the data, then filter the rows.
If you can't change the type of the field itself, you can create a persisted computed column that returns the value as a date and add indexes to it. You'll be able to use that column for indexed querying:
alter table SomeTable add date2 as TRY_convert(Actual_Date,date_str,105) PERSISTED
create index IX_SomeTable_ActualDate on SomeTable (Actual_Date)
This will allow you to perform sorting without tricks:
SELECT *
FROM SomeTable
ORDER BY Actual_Date
Or run range queries that take advantage of the IX_SomeTable_ActualDate index:
SELECT *
FROM SomeTable
Where Actual_Date Between DATEADD(d,-7,GETDATE()) AND GETDATE()
If you have 1000 rows, you could get 1000 times better performance.
Existing applications won't even notice the change. Newer queries and applications will be able to take advantage of indexing and sorting
I had a similar problem: my column (<my_date_field>) had date values in the form of
2021-01
2021-02
2021-10
2021-12
and so on, with data type of nvarchar(4000), and I always ran into the Conversion failed when converting date and/or time from character string. error (when trying e.g. CAST(<my_date_field> AS DATE) or CAST(CAST(<my_date_field> AS VARCHAR(7)) AS DATE) etc.)
I was able to convert them to date with the following code:
SELECT
CONVERT(date, <my_date_field> + '-01') AS first_day_of_month
FROM my_table
which resulted in
2021-08-01
2021-07-01
2021-06-01
2021-05-01
I have a table that has a column of dates in m/d/yyyy format stored in nvarchar(50) data types (I inherited this...). I would like to convert these columns into date data types so they are correctly stored, but can't afford to accidentally drop the data in the columns.
I've tried doing this in SQL server 2008R2, using the designer to change the data type to date. This worked for my test column (kept the dates, corrected the format, etc.) but all nulls became 1900-01-01. I can live with that but it seems there's a more eloquent solution.
However, when I tried it on the real data column, I received an error:
Unable to modify table. Conversion failed when converting date and/or time from character string.
What would be the proper way to handle this? Sorry if this is duplicate. I've been looking for an hour and haven't figured it out.
You apparently have data somewhere in the table that SQL Server is unable to convert to date. You can find the rows with a query along these lines:
SELECT * FROM TableName WHERE ISDATE(ColumnName) != 1
Obviously, you'll need to substitute TableName and ColumnName with the actual names.
Once you've identified the rows with bad data, handling it is up to you... change the data manually for each row, set them to null, whatever you feel is acceptable in this case.
I would suggest you add a new column with a Date datatype then convert/copy the data over and finally delete the original column.
what you can do is
add another column to the table of type DATETIME
Update new column values by casting the existing column values as DATETIME
Remove the existing column
Maybe you can temporally duplicate the columns with the data type of date, with this you can run an update command to convert the varchar to datetime and store it in this new columns, when you are sure that all information is correct, you can delete the columns and rename the new ones to their original name.
I always do this when I need to ensure to not lose information on change data types.
You can use following query to update your date to ISO Format (yyyymmdd) which will gurantee to work in any server. SQL SERVER - DEMO covers 4 possible cases of your date like 'd/m/yyyy','dd/m/yyyy','d/mm/yyyy' & 'dd/mm/yyyy' and update them to ISO Format
Update mytable
Set d = right(d,charindex('/',reverse(d),1)-1) +
right('0' + substring(d, charindex('/',d,1) + 1, charindex('/', d, charindex('/',d,1) + 1 ) - charindex('/',d,1) -1 ),2) +
right('0' + left(d,charindex('/',d,1)-1),2)
Or you can use this method directly in a select query as
Select id,convert(date,
right(d,charindex('/',reverse(d),1)-1) +
right('0' + substring(d, charindex('/',d,1) + 1, charindex('/', d,
charindex('/',d,1) + 1 ) - charindex('/',d,1) -1 ),2) +
right('0' + left(d,charindex('/',d,1)-1),2)
) correctDate
From mytable
I have to write an SQL view that returns the time part of a datetime column as a string in the format hhmmss (apparently SAP BW doesn't understand hh:mm:ss).
This code is the SAP recommended way to do this, but I think there must be a better, more elegant way to accomplish this
TIME = case len(convert(varchar(2), datepart(hh, timecolumn)))
when 1 then /* Hour Part of TIMES */
case convert(varchar(2), datepart(hh, timecolumn))
when '0' then '24' /* Map 00 to 24 ( TIMES ) */
else '0' + convert(varchar(1), datepart(hh, timecolumn))
end
else convert(varchar(2), datepart(hh, timecolumn))
end
+ case len(convert(varchar(2), datepart(mi, timecolumn)))
when 1 then '0' + convert(varchar(1), datepart(mi, timecolumn))
else convert(varchar(2), datepart(mi, timecolumn))
end
+ case len(convert(varchar(2), datepart(ss, timecolumn)))
when 1 then '0' + convert(varchar(1), datepart(ss, timecolumn))
else convert(varchar(2), datepart(ss, timecolumn))
end
This accomplishes the desired result, 21:10:45 is displayed as 211045.
I'd love for something more compact and easily readable but so far I've come up with nothing that works.
NOTE:
The question says that the column is of datatype DATETIME, not the newer (SQL Server 2008) TIME datatype.
ANSWER:
REPLACE(CONVERT(VARCHAR(8),timecolumn,8),':','')
Let's unpack that.
First, CONVERT formats the time portion of the datetime into a varchar, in format 'hh:mi:ss' (24-hour clock), as specified by the format style value of 8.
Next, the REPLACE function removes the colons, to get varchar in format 'hhmiss'.
That should be sufficient to get a usable string in the format you'd need.
FOLLOW-UP QUESTION
(asked by the OP question)
Is an inline expression faster/less server intensive than a user defined function?
The quick answer is yes. The longer answer is: it depends on several factors, and you really need to measure the performance to determine if that's actually true or not.
I created and executed a rudimentary test case:
-- sample table
create table tmp.dummy_datetimes (c1 datetime)
-- populate with a row for every minute between two dates
insert into tmp.dummy_datetimes
select * from udfDateTimes('2007-01-01','2009-01-01',1,'minute')
(1052641 row(s) affected)
-- verify table contents
select min(c1) as _max
, max(c1) as _min
, count(1) as _cnt
from tmp.dummy_datetimes
_cnt _min _max
------- ----------------------- -----------------------
1052641 2007-01-01 00:00:00.000 2009-01-01 00:00:00.000
(Note, the udfDateTimes function returns the set of all datetime values between two datetime values at the specified interval. In this case, I populated the dummy table with rows for each minute for two entire years. That's on the order of a million ( 2x365x24x60 ) rows.
Now, user defined function that performs the same conversion as the inline expression, using identical syntax:
CREATE FUNCTION [tmp].[udfStrippedTime] (#ad DATETIME)
RETURNS VARCHAR(6)
BEGIN
-- Purpose: format time portion of datetime argument to 'hhmiss'
-- (for performance comparison to equivalent inline expression)
-- Modified:
-- 28-MAY-2009 spencer7593
RETURN replace(convert(varchar(8),#ad,8),':','')
END
NOTE: I know the function is not defined to be DETERMINISTIC. (I think that requires the function be declared with schema binding and some other declaration, like the PRAGMA required Oracle.) But since every datetime value is unique in the table, that shouldn't matter. The function is going to have to executed for each distinct value, even if it were properly declared to be DETERMINISTIC.
I'm not a SQL Server 'user defined function' guru here, so there may be something else I missed that will inadvertently and unnecessarily slow down the function.
Okay.
So for the test, I ran each of these queries alternately, first one, then the other, over and over in succession. The elapsed time of the first run was right in line with the subsequent runs. (Often that's not the case, and we want to throw out the time for first run.) SQL Server Management Studio reports query elapsed times to the nearest second, in format hh:mi:ss, so that's what I've reported here.
-- elapsed times for inline expression
select replace(convert(varchar(8),c1,8),':','') from tmp.dummy_datetimes
00:00:10
00:00:11
00:00:10
-- elapsed times for equivalent user defined function
select tmp.udfStrippedTime(c1) from tmp.dummy_datetimes
00:00:15
00:00:15
00:00:15
For this test case, we observe that the user defined function is on the order of 45% slower than an equivalent inline expression.
HTH
you could use a user-defined function like:
create FUNCTION [dbo].[udfStrippedTime]
(
#dt datetime
)
RETURNS varchar(32)
AS
BEGIN
declare #t varchar(32)
set #t = convert( varchar(32), #dt, 108 )
set #t = left(#t,2) + substring(#t,4,2)
RETURN #t
END
then
select dbo.udfStrippedTime(GETDATE())
the logic for the seconds is left as an exercise for the reader
Here's a question. Does the formatting need to happen on the Db Server? The server itself really only care about, and is optimized for storing the data. Viewing the data is usually the responsibility of hte layer above the Db (in a strictly academic sense, the real world is a bit more messy)
For instance, if you are outputting the result into an ASP.NET page bound to a GridControl you would just specify your DataFormattingString when you bind to the column. If you were using c# to write it to a text file, when you pull the data you would just pass the format string to the .ToString() function.
If you need it to be on the DbServer specifically, then yeah pretty much every solution is going to be messy because the time format you need, while compact and logical, is not a time format the server will recognize so you will need to manipulate it as a string.
This handles the 00 - > 24 conversion
SELECT CASE WHEN DATEPART(hh,timecolumn) = 0
THEN '24' + SUBSTRING(REPLACE(CONVERT(varchar(8),timecolumn, 108),':',''),3,4)
ELSE REPLACE(CONVERT(varchar(8),timecolumn, 108),':','') END
Edit 2: updated to handle 0 --> 24 conversion, and a shorter version:
select replace(left(replace(convert(char,getdate(),8),':',''),2),'00','24') + right(replace(convert(char,getdate(),8),':',''),4)
Back to the slightly longer version :)
SELECT replace(convert(varchar(15),datetimefield, 108), ':','')
from Table
SELECT REPLACE('2009-05-27 12:49:19', ':', '')
2009-05-27 124919