Issue with scaffolding a column with DATETIME NULL ON UPDATE CURRENT_TIMESTAMP

[baronics]

The code

MySQL database schema:

CREATE TABLE IF NOT EXISTS `modTest`(
  `id` INT NOT NULL AUTO_INCREMENT,
  `modify_date1` DATETIME NULL,
  `modify_date2` DATETIME NOT NULL,
  `modify_date3` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
  `modify_date4` DATETIME NULL ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

Scaffold generated code:

public partial class CpContext : DbContext
    {
        public CpContext()
        {
        }

        public CpContext(DbContextOptions<CpContext> options)
            : base(options)
        {
        }

        public virtual DbSet<Modtest> Modtest { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            if (!optionsBuilder.IsConfigured)
            {
#warning To protect potentially sensitive information in your connection string, you should move it out of source code. See http://go.microsoft.com/fwlink/?LinkId=723263 for guidance on storing connection strings.
                optionsBuilder.UseMySql(ConnectString);
            }
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Modtest>(entity =>
            {
                entity.ToTable("modtest");

                entity.Property(e => e.Id)
                    .HasColumnName("id")
                    .HasColumnType("int(11)");

                entity.Property(e => e.ModifyDate1)
                    .HasColumnName("modify_date1")
                    .HasColumnType("datetime");

                entity.Property(e => e.ModifyDate2)
                    .HasColumnName("modify_date2")
                    .HasColumnType("datetime");

                entity.Property(e => e.ModifyDate3)
                    .HasColumnName("modify_date3")
                    .HasColumnType("datetime")
                    .HasDefaultValueSql("'CURRENT_TIMESTAMP'");

                entity.Property(e => e.ModifyDate4)
                    .HasColumnName("modify_date4")
                    .HasColumnType("datetime")
                    .();
            });

            OnModelCreatingPartial(modelBuilder);
        }

        partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
    }

The issue

The modify_date4 ON UPDATE column is generating invalid code.
The entity.Property ends with .(); which must be removed in order to compile.

Further technical details

MySQL version: 8.0.17
Operating system: Windows 10
Pomelo.EntityFrameworkCore.MySql version: 3.0.0
.NET Core 3.0.100

[baronics]

If I change

`modify_date4` DATETIME NULL ON UPDATE CURRENT_TIMESTAMP,

to

`modify_date4` DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,

then it generates:

entity.Property(e => e.ModifyDate4)
                    .HasColumnName("modify_date4")
                    .HasColumnType("datetime")
                    .HasDefaultValueSql("'CURRENT_TIMESTAMP'")
                    .ValueGeneratedOnAddOrUpdate();

[lauxjpn]

We fixed this in 3.0.0 for timestamp columns, but not for datetime columns (that do support CURRENT_TIMESTAMP since MySQL version 5.6.6.

Same goes for this line:

.HasDefaultValueSql("'CURRENT_TIMESTAMP'")

It should not contain single quotes:

.HasDefaultValueSql("CURRENT_TIMESTAMP")

The empty call is actually an EF Core issue that already got fixed for 3.1.0 (see dotnet/efcore#18579). We work around it for timestamp columns in 3.0.0 but should do the same for datetime columns.

[baronics]

I moved to EntityFrameworkCore version 3.1.0-preview3.19554.8 and also changed my column data type from DATETIME to TIMESTAMP.
Now with:

`modify_date` TIMESTAMP NULL ON UPDATE CURRENT_TIMESTAMP

I get:

entity.Property(e => e.ModifyDate)
                    .HasColumnName("modify_date")
                    .HasColumnType("timestamp")
                    .ValueGeneratedOnUpdate();

The other columns with a default TIMESTAMP value have the single quotes removed.

I plan to move to the full release version of EntityFrameworkCore before my product ships next year and hopefully the Pomelo 3.1.0 will be available then too.

[lauxjpn]

Is the current 3.0.0 version of Pomelo working with the 3.1.0 preview of EF Core?
We plan to release an official 3.1.0 version until around mid-January 2020.

[baronics]

I haven't run into any issues with them together yet.