Generate MERGE_SET event to request that sets be merged together. Both sets must exist, and originate on the same node. They must be subscribed by the same set of nodes.
declare
p_set_id alias for $1;
p_add_id alias for $2;
v_origin int4;
begin
-- ----
-- Grab the central configuration lock
-- ----
lock table sl_config_lock;
-- ----
-- Check that both sets exist and originate here
-- ----
if p_set_id = p_add_id then
raise exception 'Slony-I: merged set ids cannot be identical';
end if;
select set_origin into v_origin from sl_set
where set_id = p_set_id;
if not found then
raise exception 'Slony-I: set % not found', p_set_id;
end if;
if v_origin != getLocalNodeId('_schemadoc') then
raise exception 'Slony-I: set % does not originate on local node',
p_set_id;
end if;
select set_origin into v_origin from sl_set
where set_id = p_add_id;
if not found then
raise exception 'Slony-I: set % not found', p_add_id;
end if;
if v_origin != getLocalNodeId('_schemadoc') then
raise exception 'Slony-I: set % does not originate on local node',
p_add_id;
end if;
-- ----
-- Check that both sets are subscribed by the same set of nodes
-- ----
if exists (select true from sl_subscribe SUB1
where SUB1.sub_set = p_set_id
and SUB1.sub_receiver not in (select SUB2.sub_receiver
from sl_subscribe SUB2
where SUB2.sub_set = p_add_id))
then
raise exception 'Slony-I: subscriber lists of set % and % are different',
p_set_id, p_add_id;
end if;
if exists (select true from sl_subscribe SUB1
where SUB1.sub_set = p_add_id
and SUB1.sub_receiver not in (select SUB2.sub_receiver
from sl_subscribe SUB2
where SUB2.sub_set = p_set_id))
then
raise exception 'Slony-I: subscriber lists of set % and % are different',
p_add_id, p_set_id;
end if;
-- ----
-- Create a SYNC event, merge the sets, create a MERGE_SET event
-- ----
perform createEvent('_schemadoc', 'SYNC', NULL);
perform mergeSet_int(p_set_id, p_add_id);
return createEvent('_schemadoc', 'MERGE_SET',
p_set_id, p_add_id);
end;