Entity Framework Core 首次调用时速度太慢

Question

我有大约 40 个实体，每次编译并运行我的应用程序后，第一次调用 DbContext 都会花费近 10 秒的时间。有没有办法让它运行得更快？

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这是当用户已经登录我的应用程序时我在第一次通话时所做的事情

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页面模型

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public class CreateModel : PageModel\n{\n    private readonly IToastNotification _toastNotification;\n    private readonly ICelulaService _celulaService;\n\n    public CreateModel(IToastNotification toastNotification, ICelulaService celulaService)\n    {\n        _toastNotification = toastNotification;\n        _celulaService = celulaService;\n    }\n\n    public IList<Celula> Celulas { get; set; }\n\n    public void OnGet()\n    {\n        Celulas = _celulaService.GetAutomated();\n    }\n}\n

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服务与接口

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public interface ICelulaService\n{\n    IList<Celula> GetAutomated();\n}\n\npublic IList<Celula> GetAutomated()\n{\n    return _context.Celulas\n         .Where(c => c.Automated)\n         .ToList();\n}\n

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该模型

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[Table("hCelulas")]\npublic class Celula\n{\n    public int Id { get; set; }\n    [Required]\n    [MaxLength(10)]\n    [Display(Name = "C\xc3\xa9lula")]\n    public string Nome { get; set; }\n\n\n    public bool Automated { get; set; }\n\n    public int? CheckListId { get; set; }\n    public CheckList CheckList { get; set; }\n}\n

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数据库上下文

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public class DatabaseContext : DbContext\n{\n   public DatabaseContext(DbContextOptions<DatabaseContext> options) : base(options)\n   {\n\n   }\n\n   protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)\n   {\n\n   }\n\n   protected override void OnModelCreating(ModelBuilder modelBuilder)\n   {    \n        modelBuilder.Entity<Celula>()\n            .HasIndex(x => x.Nome)\n            .HasName("IX_Nome_Index")\n            .IsUnique();\n\n        modelBuilder.Entity<Celula>().HasData(\n            new Celula { Id = 1, Nome = "3.9.X", Automated = true, },\n            new Celula { Id = 2, Nome = "3.9.Y", Automated = true, },\n            new Celula { Id = 3, Nome = "3.9.Z", Automated = true, }\n        );\n\n   }\n   public DbSet<Celula> Celulas { get; set; }       \n}\n

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并在启动时

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services.AddDbContext<DatabaseContext>(options =>\n{                       options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection"), sqlServerOptionsAction: sqlOptions =>\n      {\n          sqlOptions.EnableRetryOnFailure(\n              maxRetryCount: 2,\n              maxRetryDelay: TimeSpan.FromSeconds(1),\n              errorNumbersToAdd: null);\n      });\n });\n

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连接字符串

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"DefaultConnection": "服务器=(localdb)\\mssqllocaldb;数据库=DatabaseTest;Trusted_Connection=True;",

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更新

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添加了一些数据，这基本上是我遇到缓慢时的数据。

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Answer 1

在 EF-core 6.0 中添加了一个新功能，允许使用编译模型.

编译后的模型可以通过点命令生成：

dotnet ef dbcontext optimize

...之后它可以在代码中使用：

dotnet ef dbcontext optimize