EF Code First提高了自引用、一对多关系的性能

我有一个 AccountGroup 其是自参考实体。一片树叶 会计组 可以包含1个或多个 Accounts .这两个实体都有 Balance 所有物每个 会计组 有一个 均衡 其为 均衡 s的子群或总和 均衡 所有帐户的s(如果是叶组)。

为了构建一个所有 会计组 s和 Account s我必须递归地遍历这个对象图,这会导致对DB的大量调用(我的意思是很多!!)。。。

有什么方法可以改进这一点,从而减少数据库调用的数量吗?

谢谢

这是精简后的代码

账户(仅属于1个账户组)

public class Account
{
    public int Id { get; set; }
    public int GroupId { get; set; }
    public string Name { get; set; }
    public decimal Balance { get; set; }
    public string AccountType { get; set; }

    public virtual AccountGroup Group { get; set; }
}

AccountGroup(具有0个或多个AccountGroup,如果是叶,则具有1个或多个子账户)

public class AccountGroup
{
    public AccountGroup()
    {
        Accounts = new HashSet<Account>();
        Groups = new HashSet<AccountGroup>();
    }

    public int Id { get; set; }
    public bool IsRoot { get { return Parent == null; } }
    public bool IsLeaf { get { return !Groups.Any(); } }
    public decimal Balance { get { return IsLeaf ? Accounts.Sum(a => a.Balance) : Groups.Sum(g => g.Balance); } } // if leaf group, get sum of all account balances, otherwise get sum of all subgroups
    public int? ParentId { get; set; }
    public string Name { get; set; }
    public string Description { get; set; }
    public virtual ISet<Account> Accounts { get; private set; }
    public virtual ISet<AccountGroup> Groups { get; private set; }
    public virtual AccountGroup Parent { get; set; }
}

呼叫代码

// start processing root groups (ones without parent)
foreach (var rootGroup in db.AccountGroups.Include(g=>g.Groups).Where(g => g.ParentId == null))
{
    TraverseAccountGroup(rootGroup, 0);
}

// recursive method
private static void TraverseAccountGroup(AccountGroup accountGroup, int level)
{
    //
    // process account group
    //
    Console.WriteLine("{0}{1} ({2})", String.Empty.PadRight(level * 2, '.'), accountGroup.Name, level);
    //
    // if subgroups exist, process recursivelly
    //
    if (accountGroup.Groups.Any())
    {
        foreach (var subGroup in accountGroup.Groups)
        {
            TraverseAccountGroup(subGroup, level + 1);
        }
    }
    //
    // otherwise, process accounts belonging to leaf subgroup
    //
    else
    {
        foreach (var account in accountGroup.Accounts)
        {
            Console.WriteLine("ACCOUNT [{0}]", account.Name);
        }
    }
}