How to create CHECK constraint Use Fluent API?

[findmoon]

I want to create a check constraint,eg gender

CREATE TABLE `test1` (
  `id` int(11)  NOT NULL AUTO_INCREMENT ,
  `gender` varchar(6) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
  CONSTRAINT `constraint_gender` CHECK (`gender` = 'male' or `gender` = 'female')
)

I don't want use migrationBuilder.Sql() create check constraints, so I want to known Weather support Create a CHECK constraint Using Fluent API ？ same as HasCheckConstraint...(I doesn't found).

Thank you for your help

[lauxjpn]

HasCheckConstraint() was added in dotnet/efcore#14673 and then fixed in dotnet/efcore#17052 for EF Core 3.0.

I successfully checked our support for this in the 3.0.0-wip branch with the following test:

using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.TestUtilities;
using MySql.Data.MySqlClient;
using Pomelo.EntityFrameworkCore.MySql.FunctionalTests.TestUtilities;
using Xunit;

namespace Pomelo.EntityFrameworkCore.MySql.FunctionalTests
{
    public class ReportedIssuesMySqlTest
        : IClassFixture<ReportedIssuesMySqlTest.ReportedIssuesMySqlFixture>
    {
        [ConditionalFact]
        public virtual void TestIssue831()
        {
            using var context = CreateContext();

            context.Set<test1>()
                .Add(new test1 { gender = "trans" });

            var outerExpection = Assert.Throws<DbUpdateException>(() => context.SaveChanges());
            var innerException = Assert.IsType<MySqlException>(outerExpection.InnerException);
            Assert.Equal(
                innerException.Message,
                "Check constraint 'constraint_gender' is violated.");
        }

        public class test1
        {
            public int id { get; set; }
            public string gender { get; set; }
        }

        public class ReportedIssuesMySqlFixture : SharedStoreFixtureBase<PoolableDbContext>
        {
            protected override void OnModelCreating(
                ModelBuilder modelBuilder,
                DbContext context)
            {
                modelBuilder.Entity<test1>(entity =>
                {
                    entity.HasKey(e => e.id);

                    entity.Property(e => e.gender)
                        .HasMaxLength(6);

                    entity.HasCheckConstraint(
                        "constraint_gender",
                        "`gender` = 'male' or `gender` = 'female'");
                });
            }

            protected override void Seed(PoolableDbContext context)
            {
                context.Set<test1>().AddRange(
                    new test1 { gender = "male" },
                    new test1 { gender = "female" }
                );

                context.SaveChanges();
            }

            protected override ITestStoreFactory TestStoreFactory
                => MySqlTestStoreFactory.Instance;

            protected override string StoreName { get; } = "ReportedIssues";
        }

        public ReportedIssuesMySqlTest(ReportedIssuesMySqlFixture fixture)
            => Fixture = fixture;

        protected ReportedIssuesMySqlFixture Fixture { get; }
        protected DbContext CreateContext() => Fixture.CreateContext();
    }
}

This test throws the following exception (wrapped in a DbUpdateException) as expected:

MySql.Data.MySqlClient.MySqlException: 'Check constraint 'constraint_gender' is violated.'

The test generates the following SQL:

CREATE TABLE `test1` (
    `id` int NOT NULL AUTO_INCREMENT,
    `gender` varchar(6) NULL,
    CONSTRAINT `PK_test1` PRIMARY KEY (`id`),
    CONSTRAINT `constraint_gender` CHECK (`gender` = 'male' or `gender` = 'female')
);

@p0='male' (Size = 6)

INSERT INTO `test1` (`gender`)
VALUES (@p0);
SELECT `id`
FROM `test1`
WHERE ROW_COUNT() = 1 AND `id` = LAST_INSERT_ID();

@p0='female' (Size = 6)

INSERT INTO `test1` (`gender`)
VALUES (@p0);
SELECT `id`
FROM `test1`
WHERE ROW_COUNT() = 1 AND `id` = LAST_INSERT_ID();