diff --git a/backend/migrations/048_vitals_baseline_source_csv.sql b/backend/migrations/048_vitals_baseline_source_csv.sql
index 7844d06..0350c89 100644
--- a/backend/migrations/048_vitals_baseline_source_csv.sql
+++ b/backend/migrations/048_vitals_baseline_source_csv.sql
@@ -1,5 +1,5 @@
 -- Universal-CSV-Import setzt source = 'csv'. Alte CHECK-Constraints kennen das nicht.
--- Namen können je nach PG-Version abweichen → alle passenden CHECK Constraints zu source droppen.
+-- Alle passenden CHECKs zu `source` droppen (PG speichert IN oder = ANY (ARRAY[...])).
 DO $$
 DECLARE
   r RECORD;
@@ -8,16 +8,22 @@ BEGIN
     SELECT c.conname
     FROM pg_constraint c
     JOIN pg_class t ON c.conrelid = t.oid
-    WHERE t.relname = 'vitals_baseline'
+    JOIN pg_namespace n ON n.oid = t.relnamespace
+    WHERE n.nspname = 'public'
+      AND t.relname = 'vitals_baseline'
       AND c.contype = 'c'
-      AND pg_get_constraintdef(c.oid) ILIKE '%source%'
-      AND pg_get_constraintdef(c.oid) ILIKE '%IN %'
+      AND (
+        c.conname = 'vitals_baseline_source_check'
+        OR COALESCE(pg_get_constraintdef(c.oid), '') ILIKE '%source%'
+      )
   LOOP
-    EXECUTE format('ALTER TABLE vitals_baseline DROP CONSTRAINT %I', r.conname);
+    EXECUTE format('ALTER TABLE public.vitals_baseline DROP CONSTRAINT %I', r.conname);
   END LOOP;
 END $$;
 
-ALTER TABLE vitals_baseline ADD CONSTRAINT vitals_baseline_source_check
+ALTER TABLE public.vitals_baseline DROP CONSTRAINT IF EXISTS vitals_baseline_source_check;
+
+ALTER TABLE public.vitals_baseline ADD CONSTRAINT vitals_baseline_source_check
     CHECK (source IN ('manual', 'apple_health', 'garmin', 'withings', 'csv'));
 
 COMMENT ON COLUMN vitals_baseline.source IS 'manual | apple_health | garmin | withings | csv (Universal-Import)';
diff --git a/backend/migrations/049_vitals_baseline_source_csv_idempotent.sql b/backend/migrations/049_vitals_baseline_source_csv_idempotent.sql
index 1eca76f..73ec928 100644
--- a/backend/migrations/049_vitals_baseline_source_csv_idempotent.sql
+++ b/backend/migrations/049_vitals_baseline_source_csv_idempotent.sql
@@ -1,4 +1,5 @@
--- Idempotent: erneute Bereinigung der source-CHECK, falls 048 zuvor nicht griff oder nur teilweise lief.
+-- Idempotent: gleicher Zielzustand wie 048, auch wenn die CHECK schon existiert (z. B. 048 DB-seitig
+-- erfolgreich, aber nicht in schema_migrations). Ein einziges DO vermeidet Mehrfach-Statement-Probleme.
 DO $$
 DECLARE
   r RECORD;
@@ -7,14 +8,23 @@ BEGIN
     SELECT c.conname
     FROM pg_constraint c
     JOIN pg_class t ON c.conrelid = t.oid
-    WHERE t.relname = 'vitals_baseline'
+    JOIN pg_namespace n ON n.oid = t.relnamespace
+    WHERE n.nspname = 'public'
+      AND t.relname = 'vitals_baseline'
       AND c.contype = 'c'
-      AND pg_get_constraintdef(c.oid) ILIKE '%source%'
-      AND pg_get_constraintdef(c.oid) ILIKE '%IN %'
+      AND (
+        c.conname = 'vitals_baseline_source_check'
+        OR COALESCE(pg_get_constraintdef(c.oid), '') ILIKE '%source%'
+      )
   LOOP
-    EXECUTE format('ALTER TABLE vitals_baseline DROP CONSTRAINT %I', r.conname);
+    EXECUTE format('ALTER TABLE public.vitals_baseline DROP CONSTRAINT %I', r.conname);
   END LOOP;
-END $$;
 
-ALTER TABLE vitals_baseline ADD CONSTRAINT vitals_baseline_source_check
-    CHECK (source IN ('manual', 'apple_health', 'garmin', 'withings', 'csv'));
+  EXECUTE $ddl$
+    ALTER TABLE public.vitals_baseline ADD CONSTRAINT vitals_baseline_source_check
+    CHECK (source IN ('manual', 'apple_health', 'garmin', 'withings', 'csv'))
+  $ddl$;
+EXCEPTION
+  WHEN duplicate_object THEN
+    NULL;
+END $$;