ok, what should do to merge it? my script is below:

  try {
    create set (id = 2, origin = 1, comment = 'Set 2 for replication');
  } on error {
    echo 'Could not create subscription set 2 for replication';
    exit -1;
  }
  set add table (set id = 2, origin = 1, id = 523, full qualified name =
'content.thread_preference', comment = 'nodesc');

  try {
    subscribe set (id = 2, provider = 1, receiver = 2, forward = yes);
    subscribe set (id = 2, provider = 1, receiver = 3, forward = yes);
  } on error {
    echo 'Could not create subscribe for replication';
    exit -1;
  }

  merge set (id = 1, add id = 2, origin = 1);

  try {
        drop set (id = 2, origin = 1);
  } on error {
        exit 1;
  }
  echo 'Set 2 droped';

thanks again for your fast reply.

regards.

On Thu, 2008-07-31 at 23:33 -0700, Jeff Frost wrote:
> On Fri, 1 Aug 2008, Yi Zhao wrote:
> 
> > yes, as you said, It's my fault that I haven't add any node to set.
> >
> > now, I have do that, but, when merge, I got:
> > <stdin>:13: Subscription set 2 created
> > <stdin>:15: Adding tables to subscription set
> > <stdin>:26: Subscribe created
> > <stdin>:28: PGRES_FATAL_ERROR select "_replication".mergeSet(1, 2);  -
> > ERROR:  Slony-I: set 2 has subscriptions in progress - cannot merge
> >
> >
> > should I stop all the slon process???
> 
> No, there is no need to stop the slons.
>