From 48172921d75f3e4511c8ae56e3bf1b071ae00244 Mon Sep 17 00:00:00 2001
From: En <huangmingen@lesingle.com>
Date: Thu, 19 Mar 2026 16:54:21 +0800
Subject: [PATCH] =?UTF-8?q?fix:=20=E4=BF=AE=E5=A4=8D=20V41=20=E8=BF=81?=
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---
 .../V41__optimize_association_tables.sql      | 45 +++++++------------
 1 file changed, 15 insertions(+), 30 deletions(-)

diff --git a/reading-platform-java/src/main/resources/db/migration/V41__optimize_association_tables.sql b/reading-platform-java/src/main/resources/db/migration/V41__optimize_association_tables.sql
index 853dca8..7d6d384 100644
--- a/reading-platform-java/src/main/resources/db/migration/V41__optimize_association_tables.sql
+++ b/reading-platform-java/src/main/resources/db/migration/V41__optimize_association_tables.sql
@@ -13,16 +13,16 @@
 -- -----------------------------------------------------
 -- 说明：纯关联表，先删后增的更新模式，不需要唯一索引兜底
 
--- 删除联合唯一索引
-ALTER TABLE `course_collection_package` DROP INDEX IF EXISTS `uk_collection_package`;
+-- 删除联合唯一索引（MySQL 不支持 IF EXISTS，直接删除）
+ALTER TABLE `course_collection_package` DROP INDEX `uk_collection_package`;
 
 -- 删除 deleted 字段
-ALTER TABLE `course_collection_package` DROP COLUMN IF EXISTS `deleted`;
+ALTER TABLE `course_collection_package` DROP COLUMN `deleted`;
 
--- 保留普通索引（提高查询性能）
+-- 添加普通索引（提高查询性能）
 ALTER TABLE `course_collection_package`
-ADD INDEX IF NOT EXISTS `idx_collection_id` (`collection_id`),
-ADD INDEX IF NOT EXISTS `idx_package_id` (`package_id`);
+ADD INDEX `idx_collection_id` (`collection_id`),
+ADD INDEX `idx_package_id` (`package_id`);
 
 -- -----------------------------------------------------
 -- 2. tenant_course（租户 - 课程关联表）
@@ -30,15 +30,15 @@ ADD INDEX IF NOT EXISTS `idx_package_id` (`package_id`);
 -- 说明：纯关联表，授权关系，不需要唯一索引兜底
 
 -- 删除联合唯一索引
-ALTER TABLE `tenant_course` DROP INDEX IF EXISTS `uk_tenant_course`;
+ALTER TABLE `tenant_course` DROP INDEX `uk_tenant_course`;
 
 -- 删除 deleted 字段
-ALTER TABLE `tenant_course` DROP COLUMN IF EXISTS `deleted`;
+ALTER TABLE `tenant_course` DROP COLUMN `deleted`;
 
--- 保留普通索引
+-- 添加普通索引
 ALTER TABLE `tenant_course`
-ADD INDEX IF NOT EXISTS `idx_tenant_id` (`tenant_id`),
-ADD INDEX IF NOT EXISTS `idx_course_id` (`course_id`);
+ADD INDEX `idx_tenant_id` (`tenant_id`),
+ADD INDEX `idx_course_id` (`course_id`);
 
 -- -----------------------------------------------------
 -- 3. class_teacher（班级 - 教师关联表）
@@ -46,24 +46,9 @@ ADD INDEX IF NOT EXISTS `idx_course_id` (`course_id`);
 -- 说明：纯关联表，不需要 deleted 字段
 
 -- 删除 deleted 字段
-ALTER TABLE `class_teacher` DROP COLUMN IF EXISTS `deleted`;
+ALTER TABLE `class_teacher` DROP COLUMN `deleted`;
 
--- 保留普通索引
+-- 添加普通索引
 ALTER TABLE `class_teacher`
-ADD INDEX IF NOT EXISTS `idx_class_id` (`class_id`),
-ADD INDEX IF NOT EXISTS `idx_teacher_id` (`teacher_id`);
-
--- -----------------------------------------------------
--- 备注：以下表保留联合唯一索引和 deleted 字段
--- -----------------------------------------------------
--- 1. parent_student（家长 - 学生关系）
---    - 关系相对稳定，有业务历史价值
---    - 保留 uk_parent_student 和 deleted 字段
---
--- 2. system_setting（系统设置）
---    - 配置表，(tenant_id, setting_key) 天然应该唯一
---    - 保留 uk_tenant_key 和 deleted 字段
---
--- 3. tenant_package（租户 - 套餐授权）
---    - 合同性质，有历史价值
---    - 保留 deleted 字段
+ADD INDEX `idx_class_id` (`class_id`),
+ADD INDEX `idx_teacher_id` (`teacher_id`);