Can a TNxSession be used in a different thread from its creating thread?

Hi

In my application, there is a master thread M, which, during the life span
of the application, spawns many other child threads, say, A1, A2... An.

When M creates its child thread, it first creates a TNxSession instance,
and passes that instance to the child thread. The child thread will use
the TNxSession instance to access a NxServer.

My question is, is there any potential problem for this relationship? Does
a TNxSession (also TNxDatabae, TNxQuery) have to be used in the SAME thread
that creates it?

Thanks

Wuping

Wuping Xin wrote:

> In my application, there is a master thread M, which, during the life span
> of the application, spawns many other child threads, say, A1, A2... An.
>
> When M creates its child thread, it first creates a TNxSession instance, and
> passes that instance to the child thread. The child thread will use the
> TNxSession instance to access a NxServer.
>
> My question is, is there any potential problem for this relationship? Does
> a TNxSession (also TNxDatabae, TNxQuery) have to be used in the SAME thread
> that creates it?

Sessions do not have an affinity to the thread that created them. You can pass
them (and any component linked to that session) freely between threads.

*BUT* you cannot access a session (which includes any component linked to it)
in the context of multiple threads concurrently.

> In my application, there is a master thread M, which, during the
> life span of the application, spawns many other child threads, say,
> A1, A2... An.

You might be interested in the TnxSessionPool class, along with the
various TnxTreadWithSession etc classes in nxdb.pas.

--
Eivind Bakkestuen [NDD]