-- =============================================
-- 调岗申请：允许「原部门」「原岗位」为空
--
-- 问题：hrm_transfer_application.current_dept_id / current_post_id 为 NOT NULL 且无默认值，
--       而客户环境 133 个员工全部没有配置岗位（hrm_employee.post_id 为 NULL），
--       前端提交调岗申请时这两个字段为空 → insert 报
--       "Field 'current_post_id' doesn't have a default value" → 调岗申请一直提交失败。
--
-- 处理：把这两列改为允许 NULL。原部门/原岗位属于「申请时的快照」，员工档案未配置时为空是合理的，
--       不应因此阻断申请。目标部门/目标岗位仍保持 NOT NULL（前端必填，属于业务必需）。
--
-- 脚本可重复执行（幂等）
-- =============================================
SET NAMES utf8mb4;

SET @sch := DATABASE();

-- 1. 原岗位允许为空
SET @nullable := (SELECT IS_NULLABLE FROM information_schema.COLUMNS
    WHERE TABLE_SCHEMA = @sch AND TABLE_NAME = 'hrm_transfer_application' AND COLUMN_NAME = 'current_post_id');
SET @sql := IF(@nullable = 'NO',
    'ALTER TABLE `hrm_transfer_application` MODIFY COLUMN `current_post_id` bigint NULL DEFAULT NULL COMMENT ''原岗位ID（员工未配置岗位时为空）''',
    'SELECT ''current_post_id 已允许为空'' AS msg');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

-- 2. 原部门允许为空
SET @nullable := (SELECT IS_NULLABLE FROM information_schema.COLUMNS
    WHERE TABLE_SCHEMA = @sch AND TABLE_NAME = 'hrm_transfer_application' AND COLUMN_NAME = 'current_dept_id');
SET @sql := IF(@nullable = 'NO',
    'ALTER TABLE `hrm_transfer_application` MODIFY COLUMN `current_dept_id` bigint NULL DEFAULT NULL COMMENT ''原部门ID（员工未配置部门时为空）''',
    'SELECT ''current_dept_id 已允许为空'' AS msg');
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

-- 3. 核对
SELECT COLUMN_NAME, COLUMN_TYPE, IS_NULLABLE, COLUMN_DEFAULT, COLUMN_COMMENT
FROM information_schema.COLUMNS
WHERE TABLE_SCHEMA = @sch AND TABLE_NAME = 'hrm_transfer_application'
  AND COLUMN_NAME IN ('current_dept_id','current_post_id','target_dept_id','target_post_id')
ORDER BY ORDINAL_POSITION;

SELECT '调岗申请 原部门/原岗位 允许为空 初始化完成' AS result;