[EFCore] AbpODataEntityController SingleResult performs full table scan, alternatives?

• Abp 3.9.0
• .Net Core 2.1
• EF Core

As the title suggests, this seems to be by design, since the AbpODataEntityController implements the Get for a single entity (e.g. http://localhost:21021/odata/Persons(11)) by calling GetAll() and then performing a Where such as :

[EnableQuery]
public virtual SingleResult<TEntity> Get([FromODataUri] TPrimaryKey key)
{
    var entity = Repository.GetAll().Where(e => e.Id.Equals(key));
    return SingleResult.Create(entity);
}

However in EfCoreRepositoryBaseOfTEntityAndTPrimaryKeys GetAll() calls GetAllIncluding() which is implemented like this:

public override IQueryable<TEntity> GetAllIncluding(params Expression<Func<TEntity, object>>[] propertySelectors)
        {
            var query = Table.AsQueryable();
            ...
            return query;
        }

Table.AsQueryable() results in a full table scan whereas the desired result is a single entity.

I’m aware that we can just override the SingleResult function in our controller in the Web.Core to query single rows for example:

[EnableQuery]
public override SingleResult<Person> Get([FromODataUri] int key)
{
    var entity = new List<Person> { _repository.Single(c => c.Pin == key) }.AsQueryable();
    return SingleResult.Create(entity);
}

However this will not include the navigation properties (e.g. Addresses) unless we explicitly reference the EFCore nuget package in our Web.Core project in order to be able to use .Include().

Is this by design? Or would your recommend a better approach to avoid a full table scan for SingleResult OData queries?

[acjh]

Depends how you map Id.

public class Person : Entity<int>
{        
    [Column("Pin")]
    public override int Id { get; set; }

    // [Key]
    // public virtual int Pin { get; set; }
}

[acjh]

Try:

- var entity = Repository.GetAll().Where(e => e.Id.Equals(key));
+ var entity = Repository.GetAll().Where(e => e.Pin.Equals(key));