/// <summary>
/// Get an entity is added to database.
/// </summary>
/// <param name="id">Entity.</param>
/// <returns>Return true if database contains this entity.</returns>
public virtual async Task <bool> ContainsAsync(Guid id)
{
return(await DbSet.CountAsync(t => t.Index == id) > 0);
}
/// <summary>
/// Get total entity count from database.
/// </summary>
/// <returns>Return total entity count number.</returns>
public virtual async Task <int> CountAsync()
{
return(await DbSet.CountAsync());
}