diff --git a/staging-diff.sql b/staging-diff.sql
index 6fb21fc..e4387f2 100644
--- a/staging-diff.sql
+++ b/staging-diff.sql
@@ -3,3 +3,35 @@ INSERT INTO user(name) VALUES('Marie');
 INSERT INTO "user_role" (user_id, role_id) VALUES((SELECT id from user where name = 'Marie'),(SELECT id FROM role where name = 'Donau Linz'));
 INSERT INTO user(name) VALUES('Philipp');
 INSERT INTO "user_role" (user_id, role_id) VALUES((SELECT id from user where name = 'Philipp'),(SELECT id FROM role where name = 'Donau Linz'));
+
+ALTER TABLE "role" ADD COLUMN "cluster" text;
+CREATE TRIGGER IF NOT EXISTS prevent_multiple_roles_same_cluster
+BEFORE INSERT ON user_role
+BEGIN
+    SELECT CASE 
+        WHEN EXISTS (
+            SELECT 1
+            FROM user_role ur
+            JOIN role r1 ON ur.role_id = r1.id
+            JOIN role r2 ON r1."cluster" = r2."cluster"
+            WHERE ur.user_id = NEW.user_id
+            AND r2.id = NEW.role_id
+            AND r1.id != NEW.role_id
+        )
+        THEN RAISE(ABORT, 'User already has a role in this cluster')
+    END;
+END;
+
+
+UPDATE role SET 'cluster'='skill' WHERE id=2;
+UPDATE role SET 'cluster'='membership_type' WHERE id=3;
+UPDATE role SET 'cluster'='skill' WHERE id=5;
+UPDATE role SET 'cluster'='skill' WHERE id=6;
+UPDATE role SET 'cluster'='membership_type' WHERE id=7;
+UPDATE role SET 'cluster'='financial' WHERE id=8;
+UPDATE role SET 'cluster'='membership_type' WHERE id=9;
+UPDATE role SET 'cluster'='membership_type' WHERE id=14;
+UPDATE role SET 'cluster'='financial' WHERE id=17;
+UPDATE role SET 'cluster'='financial' WHERE id=18;
+UPDATE role SET 'cluster'='membership_type' WHERE id=20;
+UPDATE role SET 'cluster'='membership_type' WHERE id=22;