Fix column name mismatch in multi-table CDC demo

- Fix UNRESOLVED_COLUMN error for user_id column in silver_transactions table
- Update SQL query to use correct columns: id, amount, item_count
- Remove references to non-existent columns: user_id, currency, transaction_type
- Ensure query matches actual silver table schema

Author: mkhelghati-db

product_demos/cdc-pipeline/02-CDC-CDF-full-multi-tables.py

@@ -690,15 +690,15 @@ def get_all_table_sizes():
                 print(f"         ID: {row['id']}, User: {row['name']}, Email: {row['email']}")
 
         latest_transactions = spark.sql("""
-            SELECT id, user_id, amount, currency, transaction_type 
+            SELECT id, amount, item_count 
             FROM silver_transactions 
             ORDER BY id DESC 
             LIMIT 2
         """).collect()
         if latest_transactions:
             print("      💳 Latest Transactions:")
             for row in latest_transactions:
-                print(f"         ID: {row['id']}, User: {row['user_id']}, Amount: {row['amount']} {row['currency']}")
+                print(f"         ID: {row['id']}, Amount: {row['amount']}, Items: {row['item_count']}")
 
     except Exception as e:
         print(f"   ⚠️ Error showing details: {e}")