-- 手工派车日历增加 site（现场日历）。仅更新 COMMENT，无结构变更。
-- MySQL 5.7 / utf8mb4。可重复执行。
SET NAMES utf8mb4;

SET @col_exists = (
  SELECT COUNT(*) FROM information_schema.COLUMNS
  WHERE TABLE_SCHEMA = DATABASE()
    AND TABLE_NAME = 'pl_dispatch_calendar'
    AND COLUMN_NAME = 'calendar_kind'
);
SET @ddl = IF(
  @col_exists = 1,
  'ALTER TABLE `pl_dispatch_calendar` MODIFY COLUMN `calendar_kind` varchar(16) NOT NULL DEFAULT ''acid'' COMMENT ''日历类型：acid酸派车 alkali碱派车 other其他 site现场''',
  'SELECT 1'
);
PREPARE stmt FROM @ddl;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;