diff --git a/Src/CodeSpirit.ExamApi/Services/ClientService.cs b/Src/CodeSpirit.ExamApi/Services/ClientService.cs
index 7336a6d603ec57e89d605845adc93968daf9af14..122c39d2fbe2f891e1d0b8f39da5c58bf04f0ee7 100644
--- a/Src/CodeSpirit.ExamApi/Services/ClientService.cs
+++ b/Src/CodeSpirit.ExamApi/Services/ClientService.cs
@@ -103,6 +103,9 @@ public class ClientService : IClientService
                 .Where(s => s.UserId == userId)
                 .FirstOrDefaultAsync();
 
+            if (student == null)
+                return new List<ClientExamHistoryDto>();
+
             var examHistory = await _context.ExamRecords
                 .Include(r => r.ExamSetting)
                 .ThenInclude(s => s.ExamPaper)
diff --git a/Src/CodeSpirit.ExamApi/Services/Implementations/ExamPaperService.cs b/Src/CodeSpirit.ExamApi/Services/Implementations/ExamPaperService.cs
index 99af8e19d3558ebb9dc082aacfd33abf1df7bb77..dc05fab1e2f6aa26d83b709b1ca6240e0e382649 100644
--- a/Src/CodeSpirit.ExamApi/Services/Implementations/ExamPaperService.cs
+++ b/Src/CodeSpirit.ExamApi/Services/Implementations/ExamPaperService.cs
@@ -376,6 +376,12 @@ namespace CodeSpirit.ExamApi.Services.Implementations
 
         private async Task ValidateRandomExamPaperRules(GenerateRandomExamPaperDto createDto)
         {
+            // 总分与各题型分数之和必须相等
+            if (createDto.TotalScore!= createDto.QuestionTypeRules.Sum(r => r.ScorePerQuestion & r.Count))
+            {
+                throw new AppServiceException(400, "总分与各题型分数之和必须相等");
+            }
+
             // 预先检查题库是否有足够的题目
             foreach (var typeRule in createDto.QuestionTypeRules)
             {
diff --git a/Src/CodeSpirit.ExamApi/Services/Implementations/StudentService.cs b/Src/CodeSpirit.ExamApi/Services/Implementations/StudentService.cs
index ca2d501aab02ae00d0254e47ad04ae7ab1d75d57..7a6a89a4bb9e9d76065e3597cc7e7628a7703dd4 100644
--- a/Src/CodeSpirit.ExamApi/Services/Implementations/StudentService.cs
+++ b/Src/CodeSpirit.ExamApi/Services/Implementations/StudentService.cs
@@ -171,25 +171,19 @@ public class StudentService : BaseCRUDIService<Student, StudentDto, long, Create
     protected override async Task ValidateCreateDto(CreateStudentDto createDto)
     {
         // 检查学号是否已存在
-        var existsStudentNumber = await Repository
-            .Find(x => x.StudentNumber == createDto.StudentNumber)
-            .AnyAsync();
-        if (existsStudentNumber)
+        var existsStudentNumber = Repository.Find(x => !createDto.StudentNumber.IsNullOrWhiteSpace() && x.StudentNumber == createDto.StudentNumber);
+        if (!createDto.StudentNumber.IsNullOrWhiteSpace() && await existsStudentNumber.AnyAsync())
         {
             throw new AppServiceException(400, "学号/工号已存在！");
         }
 
-        var existsIdNo = await Repository
-            .Find(x => x.IdNo == createDto.IdNo)
-            .AnyAsync();
-        if (existsIdNo)
+        var existsIdNo = Repository.Find(x => !createDto.IdNo.IsNullOrWhiteSpace() && x.IdNo == createDto.IdNo);
+        if (!createDto.IdNo.IsNullOrWhiteSpace() && await existsIdNo.AnyAsync())
         {
             throw new AppServiceException(400, "该身份证已存在！");
         }
-        var existsAdmissionTicket = await Repository
-            .Find(x => x.AdmissionTicket == createDto.AdmissionTicket)
-            .AnyAsync();
-        if (existsAdmissionTicket)
+        var existsAdmissionTicket = Repository.Find(x => !createDto.AdmissionTicket.IsNullOrWhiteSpace() && x.AdmissionTicket == createDto.AdmissionTicket);
+        if (!createDto.AdmissionTicket.IsNullOrWhiteSpace() && await existsAdmissionTicket.AnyAsync())
         {
             throw new AppServiceException(400, "该准考证已存在！");
         }
@@ -311,27 +305,21 @@ public class StudentService : BaseCRUDIService<Student, StudentDto, long, Create
     protected override async Task OnUpdating(Student entity, UpdateStudentDto updateDto)
     {
         // 检查学号是否已存在
-        var existsStudentNumber = await Repository
-            .Find(x => x.StudentNumber == updateDto.StudentNumber && x.Id != entity.Id)
-            .AnyAsync();
-        if (existsStudentNumber)
+        var existsStudentNumberQueryable = Repository.Find(x => x.StudentNumber == updateDto.StudentNumber && x.Id != entity.Id);
+        if (!updateDto.StudentNumber.IsNullOrWhiteSpace() && await existsStudentNumberQueryable.AnyAsync())
         {
             throw new AppServiceException(400, "学号/工号已存在！");
         }
-
-
-        var existsIdNo = await Repository
-            .Find(x => x.IdNo == updateDto.IdNo && x.Id != entity.Id)
-            .AnyAsync();
-        if (existsIdNo)
+        
+        var existsIdNo = Repository.Find(x => x.IdNo == updateDto.IdNo && x.Id != entity.Id);
+        if (!updateDto.IdNo.IsNullOrWhiteSpace() && await existsIdNo.AnyAsync())
         {
             throw new AppServiceException(400, "该身份证已存在！");
         }
-        var existsAdmissionTicket = await Repository
-            .Find(x => x.AdmissionTicket == updateDto.AdmissionTicket && x.Id != entity.Id)
-            .AnyAsync();
-        if (existsAdmissionTicket)
-        {
+
+        var existsAdmissionTicket = Repository.Find(x => x.AdmissionTicket == updateDto.AdmissionTicket && x.Id != entity.Id);
+        if (!updateDto.AdmissionTicket.IsNullOrWhiteSpace() && await existsAdmissionTicket.AnyAsync())
+        { 
             throw new AppServiceException(400, "该准考证已存在！");
         }
         var entityGroups = entity.StudentGroups?.Select(x => x.StudentGroupId).ToList();