diff --git a/XisongSpaceBooking_BackEnd/Configurations/SpaceBookingDbContext.cs b/XisongSpaceBooking_BackEnd/Configurations/SpaceBookingDbContext.cs
new file mode 100644
index 0000000..f6297bf
--- /dev/null
+++ b/XisongSpaceBooking_BackEnd/Configurations/SpaceBookingDbContext.cs
@@ -0,0 +1,255 @@
+using Microsoft.EntityFrameworkCore;
+using Models.Entities;
+using XisongSpaceBooking_BackEnd.Models.Entities;
+
+namespace XisongSpaceBooking_BackEnd.Configurations
+{
+    /// <summary>
+    /// 空間預約系統的資料庫內容類別
+    /// </summary>
+    public class SpaceBookingDbContext : DbContext
+    {
+        public SpaceBookingDbContext(DbContextOptions<SpaceBookingDbContext> options) : base(options)
+        {
+        }
+
+        /// <summary>
+        /// 處室資料集
+        /// </summary>
+        public DbSet<DepartmentEntity> Departments { get; set; }
+
+        /// <summary>
+        /// 身份資料集
+        /// </summary>
+        public DbSet<RoleEntity> Roles { get; set; }
+
+        /// <summary>
+        /// 帳號資料集
+        /// </summary>
+        public DbSet<AccountEntity> Accounts { get; set; }
+
+        protected override void OnModelCreating(ModelBuilder modelBuilder)
+        {
+            base.OnModelCreating(modelBuilder);
+
+            // 配置 Department 實體
+            ConfigureDepartment(modelBuilder);
+
+            // 配置 Role 實體
+            ConfigureRole(modelBuilder);
+
+            // 配置 Account 實體
+            ConfigureAccount(modelBuilder);
+        }
+
+        /// <summary>
+        /// 配置 Department 實體
+        /// </summary>
+        /// <param name="modelBuilder">模型建構器</param>
+        private static void ConfigureDepartment(ModelBuilder modelBuilder)
+        {
+            var entity = modelBuilder.Entity<DepartmentEntity>();
+
+            // 設定資料表名稱
+            entity.ToTable("departments");
+
+            // 設定主鍵
+            entity.HasKey(d => d.DepartmentId);
+            entity.Property(d => d.DepartmentId)
+                .HasColumnName("department_id")
+                .ValueGeneratedOnAdd()
+                .HasComment("處室 ID");
+
+            // 設定處室名稱
+            entity.Property(d => d.DepartmentName)
+                .HasColumnName("department_name")
+                .HasMaxLength(20)
+                .IsRequired()
+                .HasComment("處室名稱");
+        }
+
+        /// <summary>
+        /// 配置 Role 實體
+        /// </summary>
+        /// <param name="modelBuilder">模型建構器</param>
+        private static void ConfigureRole(ModelBuilder modelBuilder)
+        {
+            var entity = modelBuilder.Entity<RoleEntity>();
+
+            // 設定資料表名稱
+            entity.ToTable("roles");
+
+            // 設定主鍵
+            entity.HasKey(r => r.RoleId);
+            entity.Property(r => r.RoleId)
+                .HasColumnName("role_id")
+                .ValueGeneratedOnAdd()
+                .HasComment("身份 ID");
+
+            // 設定身份名稱
+            entity.Property(r => r.RoleName)
+                .HasColumnName("role_name")
+                .HasMaxLength(20)
+                .IsRequired()
+                .HasComment("身份名稱");
+        }
+
+        /// <summary>
+        /// 配置 Account 實體
+        /// </summary>
+        /// <param name="modelBuilder">模型建構器</param>
+        private static void ConfigureAccount(ModelBuilder modelBuilder)
+        {
+            var entity = modelBuilder.Entity<AccountEntity>();
+
+            // 設定資料表名稱
+            entity.ToTable("accounts");
+
+            // 設定主鍵
+            entity.HasKey(a => a.AccountId);
+            entity.Property(a => a.AccountId)
+                .HasColumnName("account_id")
+                .ValueGeneratedOnAdd()
+                .HasComment("帳號 ID");
+
+            // 設定使用者姓名
+            entity.Property(a => a.Name)
+                .HasColumnName("name")
+                .HasMaxLength(20)
+                .IsRequired()
+                .HasComment("使用者姓名");
+
+            // 設定帳號名稱（唯一）
+            entity.Property(a => a.Username)
+                .HasColumnName("username")
+                .HasMaxLength(20)
+                .IsRequired()
+                .HasComment("帳號名稱");
+
+            // 設定密碼
+            entity.Property(a => a.Password)
+                .HasColumnName("password")
+                .HasMaxLength(255)
+                .IsRequired()
+                .HasComment("密碼（加密）");
+
+            // 設定電子郵件（唯一）
+            entity.Property(a => a.Email)
+                .HasColumnName("email")
+                .HasMaxLength(50)
+                .IsRequired()
+                .HasComment("電子郵件");
+
+            // 設定處室 ID（外鍵）
+            entity.Property(a => a.DepartmentId)
+                .HasColumnName("department_id")
+                .IsRequired()
+                .HasComment("處室 ID");
+
+            // 設定身份 ID（外鍵）
+            entity.Property(a => a.RoleId)
+                .HasColumnName("role_id")
+                .IsRequired()
+                .HasComment("身份 ID");
+
+            // 設定帳號狀態（轉換為字串儲存）
+            entity.Property(a => a.Status)
+                .HasColumnName("status")
+                .HasConversion(
+                    v => v.ToString().ToLower(),
+                    v => Enum.Parse<AccountStatus>(v, true))
+                .HasMaxLength(20)
+                .HasDefaultValue(AccountStatus.Unverified)
+                .IsRequired()
+                .HasComment("帳號狀態");
+
+            // 設定 BaseEntity 屬性
+            entity.Property(a => a.CreatedAt)
+                .HasColumnName("created_at")
+                .HasDefaultValueSql("CURRENT_TIMESTAMP")
+                .IsRequired()
+                .HasComment("建立時間");
+
+            entity.Property(a => a.UpdatedAt)
+                .HasColumnName("updated_at")
+                .ValueGeneratedOnUpdate()
+                .HasComment("更新時間");
+
+            entity.Property(a => a.ModifiedBy)
+                .HasColumnName("modified_by")
+                .IsRequired(false)
+                .HasComment("最後修改者帳號 ID");
+
+            // 設定唯一索引
+            entity.HasIndex(a => a.Username)
+                .IsUnique()
+                .HasDatabaseName("IX_accounts_username");
+
+            entity.HasIndex(a => a.Email)
+                .IsUnique()
+                .HasDatabaseName("IX_accounts_email");
+
+            // 設定外鍵關聯
+            entity.HasOne(a => a.Department)
+                .WithMany()
+                .HasForeignKey(a => a.DepartmentId)
+                .OnDelete(DeleteBehavior.Restrict)
+                .HasConstraintName("FK_accounts_departments");
+
+            entity.HasOne(a => a.Role)
+                .WithMany()
+                .HasForeignKey(a => a.RoleId)
+                .OnDelete(DeleteBehavior.Restrict)
+                .HasConstraintName("FK_accounts_roles");
+
+            // 設定自參考外鍵（ModifiedBy）
+            entity.HasOne<AccountEntity>()
+                .WithMany()
+                .HasForeignKey(a => a.ModifiedBy)
+                .OnDelete(DeleteBehavior.SetNull)
+                .HasConstraintName("FK_accounts_modified_by");
+        }
+
+        /// <summary>
+        /// 覆寫 SaveChanges 以自動更新 UpdatedAt 欄位
+        /// </summary>
+        public override int SaveChanges()
+        {
+            UpdateTimestamps();
+            return base.SaveChanges();
+        }
+
+        /// <summary>
+        /// 覆寫 SaveChangesAsync 以自動更新 UpdatedAt 欄位
+        /// </summary>
+        public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
+        {
+            UpdateTimestamps();
+            return await base.SaveChangesAsync(cancellationToken);
+        }
+
+        /// <summary>
+        /// 更新時間戳記
+        /// </summary>
+        private void UpdateTimestamps()
+        {
+            var entries = ChangeTracker.Entries<BaseEntity>();
+
+            foreach (var entry in entries)
+            {
+                switch (entry.State)
+                {
+                    case EntityState.Added:
+                        entry.Entity.UpdatedAt = DateTime.UtcNow;
+                        break;
+
+                    case EntityState.Modified:
+                        entry.Entity.UpdatedAt = DateTime.UtcNow;
+                        // 確保 CreatedAt 不會被修改
+                        entry.Property(e => e.CreatedAt).IsModified = false;
+                        break;
+                }
+            }
+        }
+    }
+}
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