Re: Informix vs. Sybase vs. Oracle vs. (gasp) MS SQL Server

David Williams wrote:

> Imagine 1 page with 2 rows one it.
>
> 1. Page level locking
>
> User A updates row 1
> At the same time user B updates row 2. User B has to wait for
> User B to commit.

	You're forgetting latency. There's no way that you'd ever
	get immediate concurrency as in your second scenario below.

> 2. With row level locking
> User A updates row 1
> User B updates row 2 (with no waiting).
>
> How can 1 be faster than 2 if user B has to wait?

	The wait would be negligible. In scenario 2
	you also have a wait (its hidden unless you think
	about it so you won't see it). It goes like this,
	a database server services request 1 then it services
	the next request (in this case 2). The wait is
	implicit. So you don't really gain anything.



> >       For a finely tuned application, row level locking


> >       does *not* matter.

        Hey but they don't lock rows of text in a file do they?

-am Received on Tue Dec 02 1997 - 00:00:00 CET