diff --git a/src/integrations/supabase/types.ts b/src/integrations/supabase/types.ts
index c43c0e94..07122cc6 100644
--- a/src/integrations/supabase/types.ts
+++ b/src/integrations/supabase/types.ts
@@ -6458,9 +6458,11 @@ export type Database = {
       validate_submission_items_for_approval: {
         Args: { p_item_ids: string[] }
         Returns: {
+          error_code: string
           error_message: string
           invalid_item_id: string
           is_valid: boolean
+          item_details: Json
         }[]
       }
     }
diff --git a/supabase/migrations/20251107194039_a99752a6-4662-457a-b4ea-8f5c3d68c153.sql b/supabase/migrations/20251107194039_a99752a6-4662-457a-b4ea-8f5c3d68c153.sql
new file mode 100644
index 00000000..5280cf96
--- /dev/null
+++ b/supabase/migrations/20251107194039_a99752a6-4662-457a-b4ea-8f5c3d68c153.sql
@@ -0,0 +1,249 @@
+-- ============================================================================
+-- Phase 4.3: Enhanced DB Validation with Specific Error Codes and Item Details
+-- ============================================================================
+-- Drop existing function first since we're changing the return type
+DROP FUNCTION IF EXISTS validate_submission_items_for_approval(UUID[]);
+
+-- Create enhanced validation function with specific error codes and item details
+CREATE OR REPLACE FUNCTION validate_submission_items_for_approval(
+  p_item_ids UUID[]
+)
+RETURNS TABLE (
+  is_valid BOOLEAN,
+  error_message TEXT,
+  error_code TEXT,          -- ✅ NEW: Specific PostgreSQL error code
+  invalid_item_id UUID,
+  item_details JSONB        -- ✅ NEW: Item context for debugging
+)
+LANGUAGE plpgsql
+SECURITY DEFINER
+SET search_path = public
+AS $$
+DECLARE
+  v_item RECORD;
+  v_item_data JSONB;
+  v_name TEXT;
+  v_slug TEXT;
+  v_opening_date DATE;
+  v_closing_date DATE;
+  v_item_details JSONB;
+BEGIN
+  -- Validate each item
+  FOR v_item IN
+    SELECT si.* 
+    FROM submission_items si
+    WHERE si.id = ANY(p_item_ids)
+    ORDER BY si.order_index
+  LOOP
+    v_item_data := v_item.item_data;
+    v_name := v_item_data->>'name';
+    v_slug := v_item_data->>'slug';
+    
+    -- Build item details for debugging
+    v_item_details := jsonb_build_object(
+      'item_type', v_item.item_type,
+      'action_type', v_item.action_type,
+      'name', v_name,
+      'slug', v_slug,
+      'submission_id', v_item.submission_id
+    );
+    
+    -- Basic validation: Check for required fields based on item type
+    CASE v_item.item_type
+      WHEN 'park' THEN
+        -- Required fields validation
+        IF v_name IS NULL OR TRIM(v_name) = '' THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('Park name is required for "%s"', COALESCE(v_slug, 'unknown')),
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+        IF v_slug IS NULL OR TRIM(v_slug) = '' THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('Park slug is required for "%s"', COALESCE(v_name, 'unknown')),
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+        -- Date logic validation
+        v_opening_date := (v_item_data->>'opening_date')::DATE;
+        v_closing_date := (v_item_data->>'closing_date')::DATE;
+        
+        IF v_opening_date IS NOT NULL AND v_closing_date IS NOT NULL THEN
+          IF v_closing_date < v_opening_date THEN
+            RETURN QUERY SELECT 
+              false, 
+              format('Park "%s": Closing date (%s) cannot be before opening date (%s)', 
+                v_name, v_closing_date::TEXT, v_opening_date::TEXT),
+              '23514',  -- CHECK constraint violation
+              v_item.id,
+              v_item_details || jsonb_build_object(
+                'opening_date', v_opening_date,
+                'closing_date', v_closing_date
+              );
+            RETURN;
+          END IF;
+        END IF;
+        
+        -- Duplicate slug check
+        IF EXISTS (SELECT 1 FROM parks WHERE slug = v_slug) THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('Park slug "%s" already exists (name: "%s")', v_slug, v_name),
+            '23505',  -- UNIQUE violation
+            v_item.id,
+            v_item_details || jsonb_build_object('existing_slug', v_slug);
+          RETURN;
+        END IF;
+        
+      WHEN 'ride' THEN
+        -- Required fields validation
+        IF v_name IS NULL OR TRIM(v_name) = '' THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('Ride name is required for "%s"', COALESCE(v_slug, 'unknown')),
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+        IF v_slug IS NULL OR TRIM(v_slug) = '' THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('Ride slug is required for "%s"', COALESCE(v_name, 'unknown')),
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+        -- Duplicate slug check
+        IF EXISTS (SELECT 1 FROM rides WHERE slug = v_slug) THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('Ride slug "%s" already exists (name: "%s")', v_slug, v_name),
+            '23505',  -- UNIQUE violation
+            v_item.id,
+            v_item_details || jsonb_build_object('existing_slug', v_slug);
+          RETURN;
+        END IF;
+        
+      WHEN 'manufacturer', 'operator', 'designer', 'property_owner' THEN
+        -- Required fields validation
+        IF v_name IS NULL OR TRIM(v_name) = '' THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('%s name is required for "%s"', 
+              INITCAP(v_item.item_type), 
+              COALESCE(v_slug, 'unknown')),
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+        IF v_slug IS NULL OR TRIM(v_slug) = '' THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('%s slug is required for "%s"', 
+              INITCAP(v_item.item_type), 
+              COALESCE(v_name, 'unknown')),
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+        -- Duplicate slug check
+        IF EXISTS (SELECT 1 FROM companies WHERE slug = v_slug) THEN
+          RETURN QUERY SELECT 
+            false, 
+            format('%s slug "%s" already exists (name: "%s")', 
+              INITCAP(v_item.item_type), v_slug, v_name),
+            '23505',  -- UNIQUE violation
+            v_item.id,
+            v_item_details || jsonb_build_object('existing_slug', v_slug);
+          RETURN;
+        END IF;
+        
+      WHEN 'photo' THEN
+        -- Photo validation
+        IF v_item_data->>'cloudflare_image_id' IS NULL THEN
+          RETURN QUERY SELECT 
+            false, 
+            'Photo cloudflare_image_id is required',
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details || jsonb_build_object(
+              'cloudflare_image_url', v_item_data->>'cloudflare_image_url'
+            );
+          RETURN;
+        END IF;
+        
+        IF v_item_data->>'cloudflare_image_url' IS NULL THEN
+          RETURN QUERY SELECT 
+            false, 
+            'Photo cloudflare_image_url is required',
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details || jsonb_build_object(
+              'cloudflare_image_id', v_item_data->>'cloudflare_image_id'
+            );
+          RETURN;
+        END IF;
+        
+      WHEN 'timeline_event' THEN
+        -- Timeline event validation
+        IF v_item_data->>'entity_type' IS NULL THEN
+          RETURN QUERY SELECT 
+            false, 
+            'Timeline event entity_type is required',
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+        IF v_item_data->>'entity_id' IS NULL THEN
+          RETURN QUERY SELECT 
+            false, 
+            'Timeline event entity_id is required',
+            '23502',  -- NOT NULL violation
+            v_item.id,
+            v_item_details;
+          RETURN;
+        END IF;
+        
+      ELSE
+        RETURN QUERY SELECT 
+          false, 
+          format('Unknown item type: "%s"', v_item.item_type),
+          '22023',  -- Invalid parameter value
+          v_item.id,
+          v_item_details;
+        RETURN;
+    END CASE;
+  END LOOP;
+  
+  -- All items valid
+  RETURN QUERY SELECT 
+    true, 
+    NULL::TEXT, 
+    NULL::TEXT, 
+    NULL::UUID, 
+    NULL::JSONB;
+END;
+$$;
+
+COMMENT ON FUNCTION validate_submission_items_for_approval IS 
+'✅ Phase 4.3: Enhanced validation with specific error codes (23502=NOT NULL, 23505=UNIQUE, 23514=CHECK) and detailed item information for debugging';
+
+GRANT EXECUTE ON FUNCTION validate_submission_items_for_approval TO authenticated;
\ No newline at end of file