Entity Framework Core DbSet is not returning any data from database

Question

Entity Framework Core DbSet is not returning any data from database, but the database has many register.

This is the entity

public class Entity : BaseEntity
{
    public int EntityStatusId { get; set; }
    public int AddressId { get; set; }
    public string Name { get; set; }
    public string SocialReason { get; set; }
    public string CNPJ { get; set; }
    public EntityType Type { get; set; }
    public DateTime? CreationDate { get; set; }
    public bool? ReceiptDisabled { get; set; }
    public EntityStatus EntityStatus { get; set; }
    public Address Address { get; set; }
    public List<Company> Companies { get; set; }
    public List<Role> RoleList { get; set; }
}

public abstract class BaseEntity
{
    public int Id { get; set; }
}

Now this is the configuration class.

public class EntityMap : IEntityTypeConfiguration<Entity>
{
    public void Configure(EntityTypeBuilder<Entity> builder)
    {
        builder.ToTable("Entity");
        builder.HasKey(entity => entity.Id);
    
        builder
            .Property(entity => entity.EntityStatusId);
        builder
            .Property(entity => entity.AddressId);
        builder
            .Property(entity => entity.Name);
        builder
            .Property(entity => entity.SocialReason);
        builder
            .Property(entity => entity.CNPJ);
        builder
            .Property(entity => entity.Type)
            .HasConversion(x => (int)x, x => (EntityType)x);
        builder
            .Property(entity => entity.CreationDate);
        builder
            .Property(entity => entity.ReceiptDisabled);

        builder
            .HasOne(entity => entity.EntityStatus);
        builder
            .HasOne(entity => entity.Address);
    
        builder
            .HasMany(entity => entity.RoleList)
            .WithOne(x => x.Entity);
        builder
            .HasMany(entity => entity.Companies)
            .WithOne(x => x.Entity);
    }
}

And the context class.

    public class AucContext : DbContext
    {
        public AucContext(string databaseConfiguration)
        {
            _databaseConfiguration = databaseConfiguration;
        }
        
        private readonly string _databaseConfiguration;

        public DbSet<Campaign> Campaigns { get; set; }
        public DbSet<CampaignProject> CampaignProjects { get; set; }
        public DbSet<Company> Companies { get; set; }
        public DbSet<Cart> Carts { get; set; }
        public DbSet<CartItem> CartItems { get; set; }
        public DbSet<Donation> Donations { get; set; }
        public DbSet<DonationRecurrencePeriod> DonationRecurrencePeriods { get; set; }
        public DbSet<Entity> Entities { get; set; }
        public DbSet<Institution> Institutions { get; set; }
        public DbSet<PaymentMethod> PaymentMethods { get; set; }
        public DbSet<Person> People { get; set; }
        public DbSet<Project> Projects { get; set; }
        public DbSet<User> Users { get; set; }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.ApplyConfiguration(new CampaignMap());
            modelBuilder.ApplyConfiguration(new CampaignProjectMap());
            modelBuilder.ApplyConfiguration(new CompanyMap());
            modelBuilder.ApplyConfiguration(new CartMap());
            modelBuilder.ApplyConfiguration(new CartItemMap());
            modelBuilder.ApplyConfiguration(new DonationMap());
            modelBuilder.ApplyConfiguration(new DonationRecurrencePeriodMap());
            modelBuilder.ApplyConfiguration(new EntityMap());
            modelBuilder.ApplyConfiguration(new InstitutionMap());
            modelBuilder.ApplyConfiguration(new PaymentMethodMap());
            modelBuilder.ApplyConfiguration(new PersonMap());
            modelBuilder.ApplyConfiguration(new ProjectMap());
            modelBuilder.ApplyConfiguration(new UserMap());
        }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseSqlServer(_databaseConfiguration);
        }
    }

And the query was simple

var entity = context.Entities.Find(3)

this simple query is returning nothing, any ideas for what is happening?

Update

I have updated somethings since yesterday, and now i have updated the question unfortunately still don't work

OBS:. The ConnectionString it's ok, other objects just work fine.

Double-check the connection strings in your web.config/app.config and look for any config file in your actual build folder. (if Windows App or Service) Often there is an assumption that the app will be connecting to a particular server/database but with EF configured to create/update a schema, it's gone and created an empty database somewhere else. — Steve Py
The most likely reason is that the application connects to the wrong database. Check your connection string. You can use SQL Server's Profiler or Extended Events to see what commands are sent to the database. You can configure EF Core uses ILogger already to log connection events and the queries it generates. In EF Core 5 you can use LogTo to configure it to write to the Console or any other StreamWriter directly — Panagiotis Kanavos
Check the dbContext seems like initialize issue. Just try var entity = context.Entities.ToList() If doesn't work problem is context not initialized — Yaseer
Can you try add virtual for collection navigation public virtual List<Company> Companies { get; set; } public virtual List<Role> RoleList { get; set; } — Yaseer
@PanagiotisKanavos The OP hadn't included the Map registration code when he first posted the question. He just included the entity and map classes and said he got no data returning. so my original thought was that he hadn't registered the mapping for the entity. He has since updated his question. — Fran

Yinqiu Yinqiu · Accepted Answer · 2020-11-12T09:20:24

First, add Id to your Entity:

public int Id { get; set; }

Then in your DbContext:

1:In your OnModelCreating,add

modelBuilder.ApplyConfiguration(new EntityMap());

2:Add DbSet:

public DbSet<Entity> Entity { get; set; }

Re-migrate and update the database.Your code will work fine.

Entity Framework Core DbSet is not returning any data from database

2 Answers