I am using LINQ and in my database Tstamp fileld with Timestamp datatype. Now i want to fetch data from SQL by using LINQ query and it returns me Tstamp datafield value in System.Data.Linq.Binary datatype. Now i want to convert this Binary datatype value in Datetime format but how?
Add a comment
|
2 Answers
DateTime != timestamp
A SQL timestamp is a monotonically increasing number, expressed as binary. Not time. Nothing to do with time, except that they both roll ever-forwards. Which is why timestamp (as a keyword) is now deprecated (as confusing), and replaced with rowversion.
You cannot get time from a timestamp. If you want the time, store the time as datetime.
8 Comments
Gaurav Agrawal
then what is the use of timestamp datatype in SQL and why we use this?
Marc Gravell
timestamp (and rowversion, which are synonymous) are used to perform optimistic concurrency and change detection, since you can easily check via a single field if anything has changed. That is because any change to that record automatically changes the timestamp/rowversion to a new (higher) number.
user285oo6
Then can i convert the date to timestamp using to-timestamp('gps_timestamp','YYYY-MM-DD HH24:MI:SS.FF'), in sql
Marc Gravell
@user285oo6 by "timestamp", do you mean a
datetime? or do you mean a rowversion? Both are referred to as "timestamp"s, but they are very different things. What do you mean by "timestamp" ?user285oo6
datetime the one which is accurate to the nano seconds
|
The SQL timestamp is not actually a datetime data type. It is an auto-generated binary data type used for versioning your row. Therefore, it cannot be converted to a datetime value in C#.
See the MSDN article for more info.
2 Comments
Gaurav Agrawal
If we want to show timestamp value on aspx page then how we can show this value???
Jerad Rose
@Gaurav Agrawal - the timestamp data type does not usually contain data valuable for display, as it is usually just auto generated binary (somewhat random) data. If you need to store a date data type, use the datetime datatype in SQL. However, if you must display this data, you will need to convert the data to a string using something like Convert.ToBase64String()