I use SQL server 2014, i try the following query to select between two dates in the same table, the datatype is nvarchar, i executed the following query it just shows me three rows such('30/03/2015','30/04/2015','30/04/2015'),but in reality there is('29/02/2015','30/03/2015','31/04/2015','30/04/2015','30/04/2015')
select RegisteredDate
from Student
where Student.RegisteredDate between convert(nvarchar, '30/01/2014', 103)
and convert(nvarchar, '30/04/2015', 103)
Cast the other way round, other way you are comparing strings:
select RegisteredDate from Student
where convert(date, Student.RegisteredDate, 103) between '20140130' and '20150430'
The fact is that those dates saved as strings are ordered as:
'29/02/2015',
'30/03/2015',
'30/04/2015',
'30/04/2015',
'31/04/2015'
Now imagine where would you add filter values?
'29/02/2015',
'30/01/2014' --start date
/-------------\
|'30/03/2015',|
|'30/04/2015',|
|'30/04/2015',|
\-------------/
'30/04/2015' --end date
'31/04/2015'
So between will return you those three rows.
Also you have in your data 29/02/2015. In 2015 February ends on 28(you have incorrect data in tables already). You will never be able to insert such values if you choose types correctly.So the conclusion is:
Use Appropriate data types for your data!
As i have read the other answers and comments, i could recommend you to firstly change the datatype of "RegisteredDate" from "nvarchar" to "date". Secondly use this standard 'yyyy-MM-dd' below code is what you need
select RegisteredDate
from Student
where Student.RegisteredDate between '2014-01-30' and '2015-04-30'
you will not be in need of any conversions, this is how i do it for myself
Try to cast your string to date instead of casting all the dates in the table to string.
You are casting all the records in the table to string and it might be millions of them. This way not only your performance will be better but more important you will compare them to dates, not as String.
SELECT RegisteredDate
FROM Student
WHERE Student.RegisteredDate BETWEEN Convert(Date, '30/01/2014',103) AND Convert(Date, '30/04/2015', 103)
As I said in the comments, a string comparation uses alphabetical order one char after another starting from the left. For example: 20/01/1302 will be after 01/12/4016 as the "2" char goes after the "1" char in ASCII.
Update: convert Student.RegisteredDate to date if it is still in nvarchar type. I would recommend you to change the type if you can to this. It might be a source of bugs and performance problems if you do not do this.
SQL Server 2014 makes the string to dates conversion automagically but only if it needs to. Comparing a '30/04/2015' string with a nvarchar is just a String comparation.
Related
There is this strange error in sql query.
The query is something like this.
select * from student where dob between '20150820' and '20150828'
But in the database the column of dob is varchar(14) and is in yyyyMMddhhmmss format,Say my data in the row is (20150827142545).If i fire the above query it should not retrive any rows as i have mentioned yyyyMMdd format in the query.But it retrives the row with yesterday date (i.e 20150827112535) and it cannot get the records with today's date (i.e 20150828144532)
Why is this happening??
Thanks for the help in advance
You can try like this:
select * from student
where convert(date,LEFT(dob,8)) between
convert(date'20150820') and convert(date,'20150828'))
Also as others have commented you need to store your date as Date instead of varchar to avoid such problems in future.
As already mentioned you would need to use the correct date type to have between behave properly.
select *
from student
where convert(date,LEFT(dob,8)) between '20150820' and '20150828'
Sidenote: You don't have to explicitly convert your two dates from text as this will be done implicitly as long as you use an unambiguous date representation, i.e. the ISO standard 'YYYYMMDD' or 'YYYY-MM-DD'. Of course if you're holding the values in variables then use date | datetime datatype
declare #startdate date
declare #enddate date
select *
from student
where convert(date,LEFT(dob,8)) between #startdate and #enddate
Sidenote 2: Performing the functions on your table dob column would prevent any indexes on that column from being used to their full potential in your execution plan and may result in slower execution, if you can, define the correct data type for the table dob column or use a persistent computed column or materialised view if your performance is a real issue.
Sidenote 3: If you need to maintain the time portion in your data i.e. date and time of birth, use the following to ensure all records are captured;
select *
from student
where
convert(date,LEFT(dob,8)) >= '20150820'
and convert(date,LEFT(dob,8)) < dateadd(d,1,'20150828')
All you have to do is to convert first the string to date.
select *
from student
where dob between convert(date, '20150820') and convert(date, '20150828')
Why is this happening?
The comparison is executed from left to right and the order of characters is determined by the codepage in use.
Sort Order
Sort order specifies the way that data values are sorted, affecting
the results of data comparison. The sorting of data is accomplished
through collations, and it can be optimized using indexes.
https://msdn.microsoft.com/en-us/library/ms143726.aspx
There are problems with between in T-SQL.
But if you want a fast answer convert to date first and use >= <= or even datediff to compare - maybe write a between function yourself if you want the easy use like between and no care about begin and start times ...
What do BETWEEN and the devil have in common?
My problem is this (using SQL Server 2008 R2).
There is some date columns with types as datetime.
So the original intention with the column was to store a date without any time.
Then datetime was chosen as datatype.
Sure it works but as the database is also logically connected to a UML-diagram I want to use the right datatype.
An example the column Parcel.DateofArrival has the type datetime.
There maybe rows that are
2011-08-05 00:00:00.000
this is a date. But if there is rows like
2011-08-05 07:30:00.000
it is a datetime.
Now I want to find a query that list rows only containing dates, not datetime.
Any hint ?
An easy way to do this is:
select p.*
from Parcel p
where DateOfArrival = cast(DateOfArrival as Date);
By casting the value to a date, the datetime portion is lost. If the original value equals this, then there is no time component.
A way to do this would be to convert it in your select statement, for example:
SELECT CONVERT(DATE, DateOfArrival) Date, *other columns*
FROM Parcel P
Another solution, would be converting it to VARCHAR, formatting it in a yyyyMMdd format, like:
SELECT CONVERT(VARCHAR(8), DateOfArrival, 112) Date, *other columns*
FROM Parcel P
And if you want to sort it or group it, you have to use the conversion.
I hope it was helpful!
select p.*
from Parcel p
where cast(DateOfArrival as time) = '00:00'
I have date field in the database in the format 2012-03-17 19:50:08.023.
I want to create a select query which gives me the data collected in the March month.
But I am not able to achieve this.
I am trying following query.
select * from OrderHeader where
Convert(varchar,UploadDt,103) between '01/03/2013' and '31/03/2013'
and DistUserUniqueID like '6361%'
This query gives me data for all the dates.
select * from OrderHeader where
UploadDt between '01/03/2013' and '31/03/2013' and DistUserUniqueID like '6361%'
This query gives me the error as Msg 242, Level 16, State 3, Line 1
The conversion of a varchar data type to a datetime data type resulted in an out-of-range value.
Please help me resolve this.
Thanks in advance
The first query returns all dates because you are converting your column to a string. Not sure why you are doing this. So when you say BETWEEN '01/anything' AND '31/anything', when you consider it is now just a string, that is going to match all "dates" in the column, regardless of month and year, since your WHERE clause will cover every single day possible (well, with the exception of the 31st of months other than March, and the first day in January and February - so not all the data but a very large percentage). '15/11/2026', for example, is BETWEEN '01\03\2013' AND '31/03/2013'.
Think about that for a second. You have datetime data in your database, and you want to convert it to a string before you query it. Would you also convert salary to a string before comparing it? If so, the person making $70,000 will look like they are making more than the person making $690,000, since character-based sorting starts at the first character and doesn't consider length.
The second query fails because you are using a regional, ambiguous format for your dates. You may like dd/mm/yyyy but clearly your server is based on US English formatting where mm/dd/yyyy is expected.
The solution is to use a proper, unambiguous format, such as YYYYMMDD.
BETWEEN '20130301' AND '20130313'
However you shouldn't use BETWEEN - since this is a DATETIME column you should be using:
WHERE UploadDt >= '20130301'
AND UploadDt < '20130401'
(Otherwise you will miss any data from 2013-03-31 00:00:00.001 through 2013-03-31 23:59:59.997.)
If you really like BETWEEN then on 2008+ (you didn't tell us your version) you can use:
WHERE CONVERT(DATE, UploadDt) BETWEEN '20130301' AND '20130331'
More date-related tips here:
Dating Responsibly
Finally, when converting to VARCHAR (or any variable-length data types), always specify a length.
Rewrite the query as
select * from OrderHeader where
UploadDt between '01/03/2013' and '01/04/2013'
and DistUserUniqueID like '6361%'
or
select * from OrderHeader where
UploadDt between Convert(datetime,'01/03/2013', 103) and Convert(datetime,'01/04/2013',103)
and DistUserUniqueID like '6361%'
I am using MS SQLServer and trying to insert a month/year combination to a table like this:
INSERT INTO MyTable VALUES (1111, 'item_name', '9/1998')
apparently, the above command cannot work since
Conversion failed when converting date and/or time from character string.
Because 9/1998 is a bad format. I want to fix this and this column of the table will show something like:
9/1998
12/1998
(other records with month/year format)
...
Can someone help me with this?
thank you
SQL Server only supports full dates (day, month, and year) or datetimes, as you can see over on the MSDN data type list: http://msdn.microsoft.com/en-us/library/ff848733(v=sql.105).aspx
You can use a date value with a bogus day or store the value as a string, but there's no native type that just stores month/year pairs.
I see this is an old post but my recent tests confirm that storing Date or splitting the year and month to two columns (year smallint, month tinyint) results in the overall same size.
The difference will be visible when you actually need to parse the date to the filter you need (year/month).
Let me know what do you think of this solution! :)
Kind regards
You can just use "01" for the day:
INSERT INTO MyTable VALUES (1111, 'item_name', '19980901')
You can:
1) Change the column type to varchar
2) Take the supplied value and convert it to a proper format that sql server will accept before inserting, and format it back to 'M/YYYY' format when you pull the data: SELECT MONTH([myDate]) + '/' + YEAR([myDate]) ...
You may want to consider what use you will have for your data. At the moment, you're only concerned with capturing and displaying the data. However, going forward, you may need to perform date calculations on it (ie, compare the difference between two records). Because of this and also since you're about two-thirds of the way there, you might as well convert this field to a Date type. Your presentation layer can then be delegated with the task of displaying it appropriately as "MM/yyyy", a function which is available to just about any programming language or reporting platform you may be using.
if you want use date type, you should format value:
declare #a date
SELECT #a='2000-01-01'
select RIGHT( convert (varchar , #a, 103), 7) AS 'mm/yyyy'
if you want make query like SELECT * FROM...
you should use varchar instead date type.
The task:
I need to count every record in a table that was added after 07/01/2011.
Info:
There is a column in the table "Date_added" which is formatted as varchar and contains dates in format mm/dd/yyyy.
What I've tried:
I tried the following query:
SELECT count(date_added) FROM Abatements_Doc WHERE date_added >= '07/01/2011'
Unfortunately it counted any date where the month was greater than 07 regardless of the year or day. I'm at a loss as to how I should format my query to get it to read the dates properly instead of by ascii sort. In my research I discovered the CAST and CONVERT options, but am not sure how to use them, or which one I should use if any. I'm extremely new to SQL, and want to make sure I don't mess up the data in the table. I just need to get the count as specified above without altering the data in the table in any way. Any help in this regard will be very much appreciated. Thanks in advance.
I didn't test. But try convert statement.
SELECT count(date_added)
FROM Abatements_Doc
WHERE convert(datetime,date_added,1) >= convert(datetime,'07/01/2011',1)
(1) don't use mm/dd/yyyy as your date format. Use a safe and unambiguous format; the only one I trust for DATETIME/SMALLDATETIME is YYYYMMDD.
(2) change the data type in your table to DATETIME/SMALLDATETIME/DATE depending on accuracy required. Then `WHERE date_added >= '20110701' will work just fine (and will use an index on that column, if one exists).
(3) if you can't change the data type, then the following will work just fine as well (though no index will be used):
WHERE CONVERT(DATETIME, date_added, 101) >= '20110701'
Varchar can't be compared, try changing your column to date type.
Convert both date_added column values and your target date to DATETIME and compare; as in:
SELECT COUNT(1)
FROM Abatements_Doc
WHERE (CONVERT(datetime, date_added, 101)) >= CONVERT('07/01/2011', date_added, 101))