Update the initial event and span db tables

deployment/postgres-init-db/sql/tables/merlin/dataset/event.sql

@@ -6,6 +6,7 @@ create table merlin.event (
 
   value jsonb,
   topic_index integer not null,
+  span_id integer,
 
   constraint event_natural_key
     primary key (dataset_id, real_time, transaction_index, causal_time)
@@ -26,6 +27,8 @@ comment on column merlin.event.value is e''
   'The value of this event as a json blob';
 comment on column merlin.event.topic_index is e''
   'The topic of this event';
+comment on column merlin.event.span_id is e''
+  'The span of this event';
 
 create function merlin.event_integrity_function()
   returns trigger

deployment/postgres-init-db/sql/tables/merlin/dataset/span.sql

@@ -1,5 +1,5 @@
 create table merlin.span (
-  id integer generated always as identity,
+  span_id integer not null,
 
   dataset_id integer not null,
   parent_id integer null,
@@ -9,17 +9,18 @@ create table merlin.span (
   type text not null,
   attributes jsonb not null,
 
+
   constraint span_synthetic_key
-    primary key (dataset_id, id)
+    primary key (dataset_id, span_id)
 )
 partition by list (dataset_id);
 
 comment on table merlin.span is e''
   'A temporal window of interest. A span may be refined by its children, providing additional information over '
   'more specific windows.';
 
-comment on column merlin.span.id is e''
-  'The synthetic identifier for this span.';
+comment on column merlin.span.span_id is e''
+  'The id for this span.';
 comment on column merlin.span.dataset_id is e''
   'The dataset this span is part of.';
 comment on column merlin.span.parent_id is e''

deployment/postgres-init-db/sql/views/merlin/simulated_activity.sql

@@ -1,6 +1,6 @@
 create view merlin.simulated_activity as
 (
-  select span.id as id,
+  select span.span_id as id,
          sd.id as simulation_dataset_id,
          span.parent_id as parent_id,
          span.start_offset as start_offset,