Entity Framework Core 3.1 脚手架生成隐藏列

Question

I have this table that uses a temporal table. I have marked [ValidFromUtc] and [ValidTillUtc] as HIDDEN so when I scaffold the table using entity framework it will not generate these properties in the entity.

CREATE TABLE [User].[User](
    [Username] [varchar](10) NOT NULL,
    [FirstName] [nvarchar](55) NULL,
    [LastName] [nvarchar](55) NULL,
    [EmailAddress] [varchar](55) NULL,
    [IsActive] [bit] NULL,
    [ValidFromUtc] [datetime2](7) GENERATED ALWAYS AS ROW START HIDDEN NOT NULL,
    [ValidTillUtc] [datetime2](7) GENERATED ALWAYS AS ROW END HIDDEN NOT NULL,
    [ModifiedBy] [nvarchar](128) NOT NULL,
    [CreateSid] [nvarchar](128) NOT NULL,
    [LastSid]  AS (suser_sname()),
 CONSTRAINT [User_pk] PRIMARY KEY CLUSTERED 
(
    [Username] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = ON, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 80, OPTIMIZE_FOR_SEQUENTIAL_KEY = OFF) ON [PRIMARY],
    PERIOD FOR SYSTEM_TIME ([ValidFromUtc], [ValidTillUtc])
) ON [PRIMARY]
WITH
(
SYSTEM_VERSIONING = ON ( HISTORY_TABLE = [User].[UserHistory] )
)
GO

ALTER TABLE [User].[User] ADD  CONSTRAINT [DF__User_ValidFromUtc]  DEFAULT (sysutcdatetime()) FOR [ValidFromUtc]
GO

ALTER TABLE [User].[User] ADD  CONSTRAINT [DF__User_ValidTillUtc]  DEFAULT ('9999-12-31 23:59:59.9999999') FOR [ValidTillUtc]
GO

ALTER TABLE [User].[User] ADD  CONSTRAINT [DF__User_ModifiedBy]  DEFAULT (suser_sname()) FOR [ModifiedBy]
GO

ALTER TABLE [User].[User] ADD  CONSTRAINT [DF__User_CreateSid]  DEFAULT (suser_sname()) FOR [CreateSid]
GO

This works fine in ef core 2.1 when scaffolding from the database table (no hidden columns):

 modelBuilder.Entity<User>(entity =>
            {
                entity.HasKey(e => e.Username)
                    .HasName("User_pk");

                entity.ToTable("User", "User");

                entity.Property(e => e.Username)
                    .HasMaxLength(10)
                    .IsUnicode(false)
                    .ValueGeneratedNever();

                entity.Property(e => e.CreateSid)
                    .IsRequired()
                    .HasMaxLength(128)
                    .HasDefaultValueSql("(suser_sname())");

                entity.Property(e => e.EmailAddress)
                    .HasMaxLength(55)
                    .IsUnicode(false);

                entity.Property(e => e.FirstName).HasMaxLength(55);

                entity.Property(e => e.LastName).HasMaxLength(55);

                entity.Property(e => e.LastSid)
                    .HasMaxLength(128)
                    .HasComputedColumnSql("(suser_sname())");

                entity.Property(e => e.ModifiedBy)
                    .IsRequired()
                    .HasMaxLength(128)
                    .HasDefaultValueSql("(suser_sname())");
            });

But now that I have updated to ef core 3.1 it adds these columns to the entity and gives them values.

 modelBuilder.Entity<User>(entity =>
            {
                entity.HasKey(e => e.Username)
                    .HasName("User_pk");

                entity.ToTable("User", "User");

                entity.Property(e => e.Username)
                    .HasMaxLength(10)
                    .IsUnicode(false);

                entity.Property(e => e.CreateSid)
                    .IsRequired()
                    .HasMaxLength(128)
                    .HasDefaultValueSql("(suser_sname())");

                entity.Property(e => e.EmailAddress)
                    .HasMaxLength(55)
                    .IsUnicode(false);

                entity.Property(e => e.FirstName).HasMaxLength(55);

                entity.Property(e => e.LastName).HasMaxLength(55);

                entity.Property(e => e.LastSid)
                    .HasMaxLength(128)
                    .HasComputedColumnSql("(suser_sname())");

                entity.Property(e => e.ModifiedBy)
                    .IsRequired()
                    .HasMaxLength(128)
                    .HasDefaultValueSql("(suser_sname())");

                entity.Property(e => e.ValidFromUtc).HasDefaultValueSql("(sysutcdatetime())");

                entity.Property(e => e.ValidTillUtc).HasDefaultValueSql("('9999-12-31 23:59:59.9999999')");
            });

I have reviewed the breaking changes for ef core 2.1 to 3.1 but I see no mention of this.

Does anyone have any information about this change or why its now ignoring the HIDDEN property.

Answer 1

To conclude this ticket I discovered that 3.1 does not scaffold hidden fields when the compatibility level is equal or greater than 130.

In entity framework 2.1 it checks the server version (equal or greater than 13) instead of the compatibility level.

In our case we were running Sql Server 2016 (version 13) but with a lower compatibility level (120). Once we updated the compatibility level to 130 the hidden fields no longer were scaffolded.

These differences can be seen in the following files in the efCore git repo:

efCore 2.1 (line 538) https://github.com/dotnet/efcore/blob/release/2.1/src/EFCore.SqlServer/Scaffolding/Internal/SqlServerDatabaseModelFactory.cs

efCore 3.1 (line 621) https://github.com/dotnet/efcore/blob/release/3.1/src/EFCore.SqlServer/Scaffolding/Internal/SqlServerDatabaseModelFactory.cs