2025/5/6 MySQL 表主键自增 ID 不从 1 开始的问题

实体类id添加

@TableId(type = IdType.AUTO)

@Data
@TableName("announcement")
public class Announcement {
    @TableId(type = IdType.AUTO)  // 关键修改
    private Long announcementId;
    // 其他字段...
}

表sql语句

-- 1. 先删除现有表（谨慎操作，备份数据！）
DROP TABLE IF EXISTS announcement;
-- 2. 重新创建表，设置自增从 1 开始
CREATE TABLE announcement (
  announcement_id BIGINT NOT NULL AUTO_INCREMENT COMMENT '公告id',
  title VARCHAR(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '公告标题',
  content TEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci COMMENT '公告内容',
  publish_time DATETIME DEFAULT NULL COMMENT '发布时间',
  expire_time DATETIME DEFAULT NULL COMMENT '过期时间',
  target_role VARCHAR(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '目标角色',
  author_id BIGINT NOT NULL COMMENT '公告作者id',
  PRIMARY KEY (announcement_id),
  KEY fk_id (author_id),
  CONSTRAINT fk_id FOREIGN KEY (author_id) REFERENCES user (user_id)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

-- 3. 再次强制重置
ALTER TABLE announcement AUTO_INCREMENT = 1;