修复MySQL问题

tests/Jiaowu.Api.Tests/MySqlMigrationTests.cs

@@ -1,4 +1,5 @@
 using Jiaowu.Api.Infrastructure.Persistence;
+using Jiaowu.Api.Infrastructure.Exams;
 using Jiaowu.Api.Infrastructure.Teaching;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Infrastructure;
@@ -99,6 +100,21 @@ public sealed class MySqlMigrationTests
         Assert.Contains(ids[1].ToString(), sql, StringComparison.OrdinalIgnoreCase);
     }
 
+    [Fact]
+    public void MySql_invigilator_candidate_query_is_translatable_without_uuid_ordering()
+    {
+        using var db = new AppDbContext(CreateMySqlOptions());
+        var excludedTeacherId =
+            Guid.Parse("11111111-1111-1111-1111-111111111111");
+
+        var sql = InvigilatorCandidateQuery
+            .Create(db, [excludedTeacherId])
+            .ToQueryString();
+
+        Assert.Contains("Teachers", sql, StringComparison.OrdinalIgnoreCase);
+        Assert.DoesNotContain("UUID(", sql, StringComparison.OrdinalIgnoreCase);
+    }
+
     [Fact]
     public void MySql_teaching_task_roster_query_is_translatable()
     {