diff --git a/packages/database/supabase/migrations/20250616212706_generate-arity.sql b/packages/database/supabase/migrations/20250616212706_generate-arity.sql
new file mode 100644
index 000000000..8ba7dda26
--- /dev/null
+++ b/packages/database/supabase/migrations/20250616212706_generate-arity.sql
@@ -0,0 +1,35 @@
+CREATE OR REPLACE FUNCTION public.compute_arity_id(p_schema_id bigint)
+RETURNS smallint
+LANGUAGE sql
+IMMUTABLE
+AS $function$
+  SELECT COALESCE(jsonb_array_length(literal_content->'roles'), 0) FROM public."Concept" WHERE id=p_schema_id;
+$function$;
+
+CREATE OR REPLACE FUNCTION public.compute_arity_lit(lit_content jsonb)
+RETURNS smallint
+LANGUAGE sql
+IMMUTABLE
+AS $function$
+  SELECT COALESCE(jsonb_array_length(lit_content->'roles'), 0);
+$function$;
+
+CREATE OR REPLACE FUNCTION public.compute_arity_local(schema_id bigint, lit_content jsonb)
+RETURNS smallint
+LANGUAGE sql
+IMMUTABLE
+AS $function$
+  SELECT CASE WHEN schema_id IS NULL THEN compute_arity_lit(lit_content) ELSE compute_arity_id(schema_id) END;
+$function$;
+
+ALTER TABLE "public"."Concept" DROP COLUMN "arity";
+
+ALTER TABLE "public"."Concept" ADD COLUMN "arity" smallint GENERATED ALWAYS AS (compute_arity_local(schema_id, literal_content)) STORED;
+
+CREATE OR REPLACE FUNCTION public.extract_references(refs jsonb)
+RETURNS bigint []
+LANGUAGE sql
+IMMUTABLE
+AS $function$
+  SELECT COALESCE(array_agg(i::bigint), '{}') FROM (SELECT DISTINCT jsonb_array_elements(jsonb_path_query_array(refs, '$.*[*]')) i) exrefs;
+$function$;
diff --git a/packages/database/supabase/schemas/concept.sql b/packages/database/supabase/schemas/concept.sql
index 8e7ab7ddd..e42498568 100644
--- a/packages/database/supabase/schemas/concept.sql
+++ b/packages/database/supabase/schemas/concept.sql
@@ -13,9 +13,24 @@ CREATE TYPE public."EpistemicStatus" AS ENUM (
 ALTER TYPE public."EpistemicStatus" OWNER TO postgres;
 
 CREATE OR REPLACE FUNCTION extract_references(refs JSONB) RETURNS BIGINT [] LANGUAGE sql IMMUTABLE AS $$
-  SELECT COALESCE(array_agg(i::bigint), '{}') FROM (SELECT jsonb_array_elements(jsonb_path_query_array(refs, '$.*[*]')) i) exrefs;
+  SELECT COALESCE(array_agg(i::bigint), '{}') FROM (SELECT DISTINCT jsonb_array_elements(jsonb_path_query_array(refs, '$.*[*]')) i) exrefs;
 $$;
 
+CREATE OR REPLACE FUNCTION compute_arity_lit(lit_content JSONB) RETURNS smallint language sql IMMUTABLE AS $$
+  SELECT COALESCE(jsonb_array_length(lit_content->'roles'), 0);
+$$;
+
+SET check_function_bodies = false;
+CREATE OR REPLACE FUNCTION compute_arity_id(p_schema_id BIGINT) RETURNS smallint language sql IMMUTABLE AS $$
+  SELECT COALESCE(jsonb_array_length(literal_content->'roles'), 0) FROM public."Concept" WHERE id=p_schema_id;
+$$;
+SET check_function_bodies = true;
+
+CREATE OR REPLACE FUNCTION compute_arity_local(schema_id BIGINT, lit_content JSONB) RETURNS smallint language sql IMMUTABLE AS $$
+  SELECT CASE WHEN schema_id IS NULL THEN compute_arity_lit(lit_content) ELSE compute_arity_id(schema_id) END;
+$$;
+
+
 CREATE TABLE IF NOT EXISTS public."Concept" (
     id bigint DEFAULT nextval(
         'public.entity_id_seq'::regclass
@@ -27,7 +42,7 @@ CREATE TABLE IF NOT EXISTS public."Concept" (
     created timestamp without time zone NOT NULL,
     last_modified timestamp without time zone NOT NULL,
     space_id bigint NOT NULL,
-    arity smallint DEFAULT 0 NOT NULL,
+    arity smallint GENERATED ALWAYS AS (compute_arity_local(schema_id, literal_content)) STORED,
     schema_id bigint,
     literal_content jsonb NOT NULL DEFAULT '{}'::jsonb,
     reference_content jsonb NOT NULL DEFAULT '{}'::jsonb,