Many countries delayed changing over, though. England and her colonies didn't switch from Julian to Gregorian reckoning until , so for them, the skipped dates were between September 4 and September 14, Other countries switched at other times, but and are the relevant dates for the DBMSs that we're discussing. Thus, two problems arise with date arithmetic when one goes back many years. The first is, should leap years before the switch be calculated according to the Julian or the Gregorian rules?
The second problem is, when and how should the skipped days be handled? Source 1 and 2. UTC-based timestamps from those dates are now somewhat nonsensical. It would be very icky for the OS to simply refuse to handle any timestamps prior to the U. SQL Server refuses to process dates before because lots of extra special logic would be required to handle them correctly and it doesn't want to handle them wrong. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 11 years, 3 months ago. Active 1 year, 6 months ago. Viewed k times. Improve this question. Daniel Daniel 6, 6 6 gold badges 29 29 silver badges 29 29 bronze badges. Add a comment. Active Oldest Votes. The significance of the date itself though can be attributed to this man. Kalen Delaney explained the choice this way So, with 12 days lost, how can you compute dates?
Improve this answer. Martin Smith Martin Smith k 80 80 gold badges silver badges bronze badges. Also other shining attributes of this answer. On a board frequented by heavy left-brainers, this is an enjoyable read. And yes, I did go to a liberal arts college. Regarding this link : imagine someone born in Sweden on the 30th of February - they'd have never aged!
The link " missing days " is broken. Venkat - fixed now with an internet archive link — Martin Smith. Joe Stefanelli Joe Stefanelli k 17 17 gold badges silver badges bronze badges. CRMay: Tell him you plan to start work on Y10K compliance on Thursday, ; that leaves you just under 5 millennia to get it fixed. Because of this 3. For the same reason as above, comparing two SQL DateTimes with a precision to the milliseconds is not acceptable as you can see with the results of following query:.
We can be very inventive and we could imagine different solutions. So I tried to run following statement:. As I so it did not give me the expected results, I even tried to manipulate a string version to add 1 millisecond with following code then compare. Obviously, no matter the solution we can imagine, this would not work due to limitations and I came to conclusion that I had to read documentation.
This data type is extensively used, even inside SQL Server, but it has by design some limitations that everyone need to be well aware of. Consider these free tools for SQL Server that improve database developer productivity.
WITH Dates. DateStr as SourceVal ,. END as LoadOutcome. FROM Dates. END ;. Author Recent Posts. Jefferson Elias. I'm one of the rare guys out there who started to work as a DBA immediately after his graduation. So, I work at the university hospital of Liege since Initially involved in Oracle Database administration which are still under my charge , I had the opportunity to learn and manage SQL Server instances in That's the reason why I won't stop learning and share the products of my learnings.
View all posts by Jefferson Elias. Latest posts by Jefferson Elias see all. Only keeps track of nanoseconds in a day. Any additional feedback? Skip Submit. YYYY is four digits from through that represent a year. MM is two digits, ranging from 01 to 12, that represent a month in the specified year. DD is two digits, ranging from 01 to 31 depending on the month, that represent a day of the specified month. You can specify date data with a numeric month specified. If the order doesn't match the setting, the values aren't interpreted as dates.
Out-of-order dates may be misinterpreted as out of range or with wrong values. A four-part year is interpreted as the year. You can specify date data with a month specified as the full month name. For example, April or the month abbreviation of Apr specified in the current language; commas are optional and capitalization is ignored.
Here are some guidelines for using alphabetical date formats: 1 Enclose the date and time data in single quotation marks '. For languages other than English, use N' 2 Characters that are enclosed in brackets are optional. Values greater than or equal to the value of this option are in the century that comes before the cutoff year.
For example, if two digit year cutoff is default , 25 is interpreted as and 50 is interpreted as To avoid ambiguity, use four-digit years. Examples: 1 T 2 T The brackets indicate that the fraction of second component is optional.
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