fix:参赛选手加入编号

src/main/java/com/ai/da/service/impl/GlobalAwardServiceImpl.java

@@ -158,14 +158,8 @@ public class GlobalAwardServiceImpl implements GlobalAwardService {
 
         LocalDateTime now = LocalDateTime.now();
         if (existing == null) {
-            // 生成唯一的参赛选手编号（从10000开始），使用数据库行锁保证并发安全与原子性
-            QueryWrapper<Contestant> numQw = new QueryWrapper<>();
-            numQw.isNotNull("contestant_number").orderByDesc("contestant_number").last("FOR UPDATE");
-            Contestant maxRow = contestantMapper.selectOne(numQw);
-            Integer nextContestantNumber = (maxRow == null || maxRow.getContestantNumber() == null) ? 10000 : maxRow.getContestantNumber() + 1;
-
+            // 由数据库自增分配 contestant_number（请确保数据库列为 AUTO_INCREMENT）
             Contestant toInsert = Contestant.builder()
-                    .contestantNumber(nextContestantNumber)
                     .email(request.getEmail())
                     .firstName(request.getFirstName())
                     .lastName(request.getLastName())
@@ -182,8 +176,11 @@ public class GlobalAwardServiceImpl implements GlobalAwardService {
                     .updatedAt(now)
                     .build();
             contestantMapper.insert(toInsert);
+            // 重新查询以获取数据库分配的 contestant_number
+            Contestant saved = contestantMapper.selectById(toInsert.getId());
+            Integer assignedNumber = (saved == null) ? null : saved.getContestantNumber();
             resp.put("success", true);
-            resp.put("contestant_number", nextContestantNumber);
+            resp.put("contestant_number", assignedNumber);
             sendSiteMsg(toInsert.getId(), toInsert.getEmail());
             return resp;
         } else {