-- mysql
alter table content_collection add column item_id bigint unsigned NOT NULL AUTO_INCREMENT,
   ADD PRIMARY KEY (item_id),
   add unique index cc_collection_id ( collection_id ),
   add column parent_id bigint unsigned;
update content_collection t1 join content_collection t2 on t1.in_collection=t2.collection_id set t1.parent_id = t2.item_id;

alter table content_resource add column item_id bigint unsigned NOT NULL AUTO_INCREMENT,
   ADD PRIMARY KEY (item_id),
   add unique index cr_resource_id ( resource_id ),
   add column parent_id bigint unsigned;
update content_resource t1 join content_collection t2 on t1.in_collection=t2.collection_id set t1.parent_id = t2.item_id;   
   
create trigger cc_parent_id_trig 
	before insert on content_collection 
	for each row 
	set new.parent_id = (select t1.item_id from content_collection as t1 where NEW.in_collection = t1.collection_id);

create trigger cr_parent_id_trig 
	before insert on content_resource 
	for each row 
	set new.parent_id = (select t1.item_id from content_collection as t1 where NEW.in_collection = t1.collection_id);

-- select t1.item_id,t2.item_id, t1.parent_id, t1.collection_id, t2.collection_id from content_collection t1 join content_collection t2 on t1.in_collection=t2.collection_id;

-- select t1.item_id,t2.item_id, t1.parent_id, t1.resource_id, t2.collection_id from content_resource t1 join content_collection t2 on t1.in_collection=t2.collection_id;