Hi,

> MT> Transactions and deadlocks... If the columns aren't too long, a
> MT> UNIQUE or PRIMARY KEY constraint.
>
> So you suggest I perform some INSERT even if I only need to update
> some rows in a serialized way?
> Well, it should work, but I don't like it too much...
>

There are many ways to solve such a problem. One way to make sure
that only ONE thread is downloading from a single host is simply putting
a constraint on the host name and continueing to the next host if you
cannot insert into the table - that way you know that some other thread
is already searching that host.

Martijn Tonies
InterBase Workbench - the developer tool for InterBase and Firebird
http://www.interbaseworkbench.com

Upscene Productions
http://www.upscene.com

"This is an object-oriented system.
If we change anything, the users object."