I am running a select against a datetime column in SQL Server 2005. I can select only the date from this datetime column?
Best way is:
SELECT DATEADD(day, DATEDIFF(Day, 0, #ADate), 0)
This is because internally, SQL Server stores all dates as two integers, of which the first one is the ****number of days*** since 1 Jan 1900. (the second one is the time portion, stored as the number of seconds since Midnight. (seconds for SmallDateTimes, or milleseconds for DateTimes)
Using the above expression is better because it avoids all conversions, directly reading and accessing that first integer in a dates internal representation without having to perform any processing... the two zeroes in the above expression (which represent 1 Jan 1900), are also directly utilized w/o processing or conversion, because they match the SQL server internal representation of the date 1 jan 1900 exactly as presented (as an integer)..
*NOTE. Actually, the number of date boundaries (midnights) you have to cross to get from the one date to the other.
Yes, by using the convert function. For example:
select getdate(), convert(varchar(10),getdate(),120)
RESULTS:
----------------------- ----------
2010-05-21 13:43:23.117 2010-05-21
You can use the functions:
day(date)
month(date)
year(date)
Also the Datepart() function might be of some use:
http://msdn.microsoft.com/en-us/library/ms174420(SQL.90).aspx
DECLARE #dToday DATETIME
SET #dToday = CONVERT(nvarchar(20), GETDATE(), 101)
SELECT #dToday AS Today
This returns today's date at 12:00am : '2010-05-21 00:00:00.000'
Then you can use the #dToday variable in a query as needed
CONVERT (date, GETUTCDATE())
CONVERT (date, GETDATE())
CONVERT (date, '2022-18-01')
I don't know why the others recommend it with varchar(x) tbh.
https://learn.microsoft.com/de-de/sql/t-sql/functions/getdate-transact-sql
Related
I have a date in format dd/mm/yyyy. I want to subtract one month from it.
I am using this code but the output is "09/10/2020" I don't know why my code does the subtraction of the year -2 also.
This is my request
SELECT
FORMAT(CONVERT (DATE, DATEADD(MONTH, -1, CONVERT(char(9), GETDATE()))), 'dd/MM/yyyy')
you need to change it to:
select format(CONVERT (date,DATEADD(MONTH, -1,GETDATE())), 'dd/MM/yyyy' )
but as Larnu stated. it seems like you need to change the column.
Your current code doesn't work as expected because:
SELECT CONVERT(char(9), GETDATE());
Returns this (at least in my language):
Nov 9 20
Which is, unfortunately, and again in my language, a valid date (but in {20}20, not {20}22).
Even in the right style (103), char(9) would yield 10/11/202 tomorrow, since 9 digits is only enough if either the day or month is a single digit.
Don't know why you are converting GETDATE() to a string. Just perform date math on it and then format it if you need to (using a specific style number, e.g. 103 for d/m/y):
SELECT CONVERT(char(10), DATEADD(MONTH, -1, GETDATE()), 103);
I really wouldn't use FORMAT() for such simple output, as the CLR overhead really isn't worth it. Ideally you leave it as a date/time type until presentation time - surely your presentation layer can present your date as d/m/y if that's really a wise idea.
And if you are storing or passing dates as strings (and worse, in regional formats like d/m/y) you really should consider fixing that.
First of all,
You should be storing your Date as a string for easier manipulation. If you don't want to change the column, you can always convert from Date to Varchar and then (re)convert it.
Example:
First, convert Date to varchar using the style code '112' ISO for formatting as yyyyMMdd:
DECLARE #date DATE = GETDATE();
DECLARE #dateConverted as VARCHAR (8) = (SELECT CONVERT(VARCHAR, #date, 112));
Then you just subtract the month using DATEADD():
DECLARE #previousMonth AS VARCHAR (8) = (SELECT FORMAT(DATEADD(month, -1, #dateConverted), 'yyyyMMdd'));
Finally, convert varchar do Date again:
DECLARE #previousMonthConverted AS DATE = (SELECT CONVERT(CHAR(10), CONVERT(date, #previousMonth), 120));
NPD.CreatedOn is defined as a datetime datatype column (in SQL Server).
SELECT *
FROM NPDMaster NPD
WHERE DATEDIFF(MONTH, CONVERT(VARCHAR(7), NPD.CreatedOn, 126), CONVERT(VARCHAR(30), GETDATE(), 126)) <= 6
I get this error:
Conversion failed when converting date and/or time from character string.
What can I try to resolve it?
Don't use things like DATEDIFF in the WHERE on your columns, such queries aren't SARGable and thus can (will) perform poorly. If you want rows where the date is on or after the start of the month 6 months ago then do the date logic on GETDATE()/SYSDATETIME()/etc:
SQL Server doesn't have a "start of month" function, but you can use EOMONTH and then add a day:
SELECT *
FROM dbo.NPDMaster NPD
WHERE NPD.CreatedOn >= DATEADD(DAY, 1, EOMONTH(GETDATE(),-7));
You don't need to convert the datetime values to text. DATEDIFF() expects datetime values as second and third argument:
SELECT *
FROM NPDMaster NPD
WHERE DATEDIFF(month, NPD.CreatedOn, GETDATE()) <= 6
The actual reason for the error (as is explained in the documentation), is that ...DATEDIFF implicitly casts string literals as a datetime2 type.
In a SQL Server query, I am currently using the clause
WHERE
DAY(trade_date) = DAY(GETDATE()) - 1
AND MONTH(trade_date) = MONTH(GETDATE())
AND YEAR(trade_date) = YEAR(GETDATE())
to query my data from the previous day.
It is working fine right now but my question is if, for example, on 8/1/2021, SQL Server will try to get data from 8/0/2021 or if it will know to get data from 7/31/2021.
If this query won't work what could I use instead? Thanks!
I would recommend using proper date comparison logic - instead of breaking it down to day, month and year. Also, it is recommended to use proper date arithmetic functions like DATEADD instead of just - 1 on your date values (never sure what that -1 stands for: minus one day? Week? Month? Hour?).
And lastly - I would also recommend using SYSDATETIME() instead of GETDATE() since the latter always returns a DATETIME datatype - which should be on its way out, and you should use DATE (if you don't need to time portion), or DATETIME2(n) (if you do need the time portion) since those are more efficient and have fewer limitations compared to DATETIME.
If your trade_date is a DATE column (as it probably should be), just use:
WHERE
trade_date = DATEADD(DAY, -1, SYSDATETIME())
and if it's not a DATE - just cast it to a date as needed:
WHERE
CAST(trade_date AS DATE) = DATEADD(DAY, -1, CAST(SYSDATETIME() AS DATE))
Ii have values stored in the SQL Server in the following manner : 02-Jul-12 12:00:00 AM here the time and minutes, seconds can be anything like 02-Jul-12 12:15:52 PM ,02-Jul-12 6:02:12 AM so on.
I want to have a where condition which will omit the time and take the data based on the date like the following where some_Date='02-Jul-12'
How would I do this?
SELECT * FROM whatever WHERE some_Date LIKE '02-Jul-12%';
If you are on SQL2008 or later, you can cast your DATETIME to DATE.
See this post: http://blog.sqlauthority.com/2012/09/12/sql-server-get-date-and-time-from-current-datetime-sql-in-sixty-seconds-025-video/
But in a WHERE-clause it is better to search between dates, like this:
DECLARE #startDate DATETIME = '02-Jul-2012'
DECLARE #endDate DATETIME = DATEADD(DAY, 1, #startDate)
SELECT * FROM [table] WHERE [some_Date] BETWEEN #startDate AND #endDate
SELECT * FROM dbo.tbl_MyTable
WHERE
REPLACE(CONVERT(VARCHAR(9), DateTimeValueColumn, 6), ' ', '-')='02-Jul-12'
or
On chage in code is instead of using getdate function voncert you datestring in datetime format and do compare this follow query will work for you
SELECT * FROM dbo.tbl_MyTable
WHERE
CAST(CONVERT(CHAR(10), DateTimeValueColumn, 102) AS DATE) =
CAST(CONVERT(CHAR(10),GETDATE(),102) AS DATE)
If you are storing dates as characters -- which is not recommended -- you should at least use ISO format: YYYY-MM-DD hh:mm:ss. This makes the date useful for sorting and comparisons ("<" works, ">" works, "between" works as well as equals).
To extract the date, you can then use left(datestr, 10). In your format, you would use:
where left(datestr, 9) = '01-Jan-13'
If you are storing the fields as a datetime or smalldatetime, you may think they are stored as a string. They are not. They are stored as some number of days since some particular date, with day parts stored as fractional days. If you are using SQL Server 2005 or greater, then the best way is:
where cast(datetime as date) = '2013-01-01' -- I recommend ISO formats, even for constants. '20130101' is even better
To select rows with today's date (not time)
select * from myTable where datediff(dd, dateColumn, getdate()) = 0
I have two tables where column [date] is type of DATETIME2(0).
I have to compare two records only by theirs Date parts (day+month+year), discarding Time parts (hours+minutes+seconds).
How can I do that?
Use the CAST to the new DATE data type in SQL Server 2008 to compare just the date portion:
IF CAST(DateField1 AS DATE) = CAST(DateField2 AS DATE)
A small drawback in Marc's answer is that both datefields have been typecast, meaning you'll be unable to leverage any indexes.
So, if there is a need to write a query that can benefit from an index on a date field, then the following (rather convoluted) approach is necessary.
The indexed datefield (call it DF1) must be untouched by any kind of function.
So you have to compare DF1 to the full range of datetime values for the day of DF2.
That is from the date-part of DF2, to the date-part of the day after DF2.
I.e. (DF1 >= CAST(DF2 AS DATE)) AND (DF1 < DATEADD(dd, 1, CAST(DF2 AS DATE)))
NOTE: It is very important that the comparison is >= (equality allowed) to the date of DF2, and (strictly) < the day after DF2. Also the BETWEEN operator doesn't work because it permits equality on both sides.
PS: Another means of extracting the date only (in older versions of SQL Server) is to use a trick of how the date is represented internally.
Cast the date as a float.
Truncate the fractional part
Cast the value back to a datetime
I.e. CAST(FLOOR(CAST(DF2 AS FLOAT)) AS DATETIME)
Though I upvoted the answer marked as correct. I wanted to touch on a few things for anyone stumbling upon this.
In general, if you're filtering specifically on Date values alone. Microsoft recommends using the language neutral format of ymd or y-m-d.
Note that the form '2007-02-12' is considered language-neutral only
for the data types DATE, DATETIME2, and DATETIMEOFFSET.
To do a date comparison using the aforementioned approach is simple. Consider the following, contrived example.
--112 is ISO format 'YYYYMMDD'
declare #filterDate char(8) = CONVERT(char(8), GETDATE(), 112)
select
*
from
Sales.Orders
where
CONVERT(char(8), OrderDate, 112) = #filterDate
In a perfect world, performing any manipulation to the filtered column should be avoided because this can prevent SQL Server from using indexes efficiently. That said, if the data you're storing is only ever concerned with the date and not time, consider storing as DATETIME with midnight as the time. Because:
When SQL Server converts the literal to the filtered column’s type, it
assumes midnight when a time part isn’t indicated. If you want such a
filter to return all rows from the specified date, you need to ensure
that you store all values with midnight as the time.
Thus, assuming you are only concerned with date, and store your data as such. The above query can be simplified to:
--112 is ISO format 'YYYYMMDD'
declare #filterDate char(8) = CONVERT(char(8), GETDATE(), 112)
select
*
from
Sales.Orders
where
OrderDate = #filterDate
You can try this one
CONVERT(DATE, GETDATE()) = CONVERT(DATE,'2017-11-16 21:57:20.000')
I test that for MS SQL 2014 by following code
select case when CONVERT(DATE, GETDATE()) = CONVERT(DATE,'2017-11-16 21:57:20.000') then 'ok'
else '' end
You may use DateDiff and compare by day.
DateDiff(dd,#date1,#date2) > 0
It means #date2 > #date1
For example :
select DateDiff(dd, '01/01/2021 10:20:00', '02/01/2021 10:20:00')
has the result : 1
For Compare two date like MM/DD/YYYY to MM/DD/YYYY .
Remember First thing column type of Field must be dateTime.
Example : columnName : payment_date dataType : DateTime .
after that you can easily compare it.
Query is :
select * from demo_date where date >= '3/1/2015' and date <= '3/31/2015'.
It very simple ......
It tested it.....