SQL Server time stamp column insertion or updation possible explicitly? - sql-server

Question

Is there any way to provide an explicit value for time stamp column in a table in SQL server? I am aware it is not datetime column but I want to know whether there is any way to insert or update it explicitly.

Answer 1

You cannot insert/update to timestamp column explicitly. They are generated automatically, when you perform insert/update to the table.

Answer 2

Because the timestamps appear to be representations of timestamps created by the database when you inserted or updated the column, in effect you would have to change the original timestamp created by the database in order to define them explicitly.
From your second comment I appreciate that you might have data coming in which is already timestamped and you just want those represented on your table in the same way as inserting data with "set identity_insert on" .
The answer would be to select the existing table into another table then add the incoming data. If you run the code below I think you'll see what I mean.
create table abc
(
col1 int, timestamp
)
go
insert into abc(col1) values (1)
go
select col1,convert(varbinary,timestamp) timestamp# into def from abc
go
select * from abc
select * from def

Answer 3

As far as I know the timestamp represents a row version number (which is why they change when you update a value in the row because you are creating another version of the row). There might be a date in the transaction log which states when this version of the row came into being. I don't consider it possible to directly convert timestamp to datetime.
Well..the only other idea I have is to add another column and then select the timestamp values into that! The weirdest thing, in doing this it takes the last character back one! See what you think.
drop table abc
go
create table abc
(
col1 int, timestamp
)
go
insert into abc(col1) values (1)
go
alter table abc add timestamp# varbinary(18)
go
update abc set timestamp# = convert(varbinary,timestamp)
Generaly speaking, when creating a table I would include a column which defaults to datetime, this way you have a datetime when each row is created.
Like this:
drop table def
go
create table def
(
col1 int,
idt datetime default getdate()
)
If you insert a value into col1 and do not include the idt in your column list in the insert statement the idt column will default to the datetime you inserted the value.
Like this:
insert into def (col1) values (1)