Re: Rowid, whatfor?

The rowid is a way to uniquyely identify a row. It is the quickest method of refering to a row. Why? Because indexes store the rowid, which is Oracle's native method for looking up a row. In a for update by current you are really using a rowid - it is just hidden from you Oracle is handling that "behind the scenes". So if you are using that method of updating then you don't need to know the rowid and should probably leave it out of your field list. (it is just taking up memory in your cursor)

If however you are not writing pl/sql and instead are writing an application with a GUI then the rowid has some potential uses. You can retrieve it and if the user wants to update or delete a row you can refer to that row directly - very effecient especially if you use host variables.

Jim

"T.Ruschival" <t.ruschival_at_vivid-md.de> wrote in message news:B748157D.3B00%t.ruschival_at_vivid-md.de...
> Hello DB-Developers
>
> Well I´m a greenhorn to Oracle PL/SQL. I read a lot but I don´t understand
> some issues. For example the Rowid.
> To obtain the Rowid I have to state a Select-Query, then I can find out
 the
> Ids of the Rows returned by that Statement. At this Moment I know the
> selected Rows already an I can refer to it for update by cursor.current .
> What is the Rowid good for? i don´t understand why everybody writes about
> this in every book?
> Please give me a hint about what I can do with this suspicios ID.
>
> Thanks Thomas
>
Received on Sat Jun 09 2001 - 12:21:00 CDT