-- Add date_manufacturer and expiry_date to the main batch data table (only if missing).
-- Run this entire script once. "Duplicate column name" for a column means it already exists — skip that ALTER.
-- These store the scanned MN date and Exp date from QR; batch_no is auto-generated by the backend.

-- Add date_manufacturer (skip if you get: Duplicate column name 'date_manufacturer')
ALTER TABLE `data`
  ADD COLUMN `date_manufacturer` VARCHAR(20) NULL COMMENT 'Manufacturing date from scan (YYYY-MM-DD)' AFTER `shift`;

-- Add expiry_date (skip if you get: Duplicate column name 'expiry_date')
ALTER TABLE `data`
  ADD COLUMN `expiry_date` VARCHAR(20) NULL COMMENT 'Expiry date from scan (YYYY-MM-DD)' AFTER `date_manufacturer`;
