Re: oracle sequence numbers

Pablo Sanchez <pablo_at_dev.null> wrote in message news:<Xns93058A335DCEFpingottpingottbah_at_216.166.71.233>...
> rhairgroveNoSpam_at_Pleasebigfoot.com (Bob Hairgrove) wrote in
> news:3e2707f5.1213124_at_news.webshuttle.ch:
>
> > On Thu, 16 Jan 2003 09:40:02 -0600, Pablo Sanchez <pablo_at_dev.null>
> > wrote:
> >
> >>Even worst, some DBMS update the timestamp any time the row is
> >>affected since the timestamp data type is used for other purposes.
> >
> > Huh??
> >
> > Once you have written a value to a column, it should stay the same
> > (unless you have a trigger implemented to update it)...
>
> Which DBMS are you thinking about? Sybase ASE and (not suprisingly)
> SQL Server both behave this way.
>
Microsoft's "SQL Server Books Online: Transact-SQL Reference" says

timestamp
timestamp is a data type that exposes automatically generated binary numbers, which are guaranteed to be unique within a database. timestamp is used typically as a mechanism for version-stamping table rows. The storage size is 8 bytes.

Remarks
The Transact-SQL timestamp data type is not the same as the timestamp data type defined in the SQL-92 standard. The SQL-92 timestamp data type is equivalent to the Transact-SQL datetime data type.

A future release of MicrosoftR SQL Server? may modify the behavior of the Transact-SQL timestamp data type to align it with the behavior defined in the standard. At that time, the current timestamp data type will be replaced with a rowversion data type. Received on Fri Jan 17 2003 - 04:13:24 CET