7

我有这个使用 QueryOver API 的存储库方法

    public IList<Message> ListMessagesBy(string text, IList<Tag> tags, int pageIndex, out int count, out int pageSize)
    {
        pageSize = 10;
        var likeString = string.Format("%{0}%", text);
        var query = session.QueryOver<Message>()
            .Where(Restrictions.On<Message>(m => m.Text).IsLike(likeString) ||
            Restrictions.On<Message>(m => m.Fullname).IsLike(likeString));

        if (tags.Count > 0)
        {
            var tagIds = tags.Select(t => t.Id).ToList();
            query
                .JoinQueryOver<Tag>(m => m.Tags)
                .WhereRestrictionOn(t => t.Id).IsInG(tagIds)
                .TransformUsing(Transformers.DistinctRootEntity);
        }                        

        count = 0;
        if(pageIndex < 0)
        {
            count = query.ToRowCountQuery().FutureValue<int>().Value;
            pageIndex = 0;
        }
        return query.OrderBy(m => m.Created).Desc.Skip(pageIndex * pageSize).Take(pageSize).List();
    }

我都试过了

.TransformUsing(Transformers.DistinctRootEntity);

和

.RootCriteria.SetResultTransformer(new DistinctEntityRootTransformer())

它搞砸了总计数（它返回的结果没有区别）和实际分页（跳过/采取）

我怎样才能解决这个问题？

提前致谢， 安德斯

4

2 回答 2

2

尝试这样的事情

public IPagedList<Client> Find(int pageIndex, int pageSize)
{
    Client clientAlias = null;

    var query = Session.QueryOver<Client>(() => clientAlias)

        .Select(
            Projections.Distinct(
                Projections.ProjectionList()
                    .Add(Projections.Property<Client>(x => x.Id).As("Id"))
                    .Add(Projections.Property<Client>(x => x.Name).As("Name"))
                    .Add(Projections.Property<Client>(x => x.Surname).As("Surname"))
                    .Add(Projections.Property<Client>(x => x.GivenName).As("GivenName"))
                    .Add(Projections.Property<Client>(x => x.EmailAddress).As("EmailAddress"))
                    .Add(Projections.Property<Client>(x => x.MobilePhone).As("MobilePhone"))
            )
        )
        .TransformUsing(Transformers.AliasToBean<Client>())

        .OrderBy(() => clientAlias.Surname).Asc
        .ThenBy(() => clientAlias.GivenName).Asc;

    var count = query
        .ToRowCountQuery()
        .FutureValue<int>();

    return query
        .Take(pageSize)
        .Skip(Pagination.FirstResult(pageIndex, pageSize))
        .List<Client>()
        .ToPagedList(pageIndex, pageSize, count.Value);
}
于 2011-02-24T00:34:25.713 回答
2

我也有这个问题。首先 Distinct 确实有效，但仅在调用 QueryOver.List.ToList() 方法之后，因此 query.skip 无法正常工作，对重复项进行分页，创建列表，然后由于重复项而减少我的分页量.

我发现做的最简单的事情是..只需先创建一个唯一ID列表，然后对ID本身进行分页..

然后在您的结果集上，您可以简单地执行一个 Id 并仅在新分页的 id 结果集中检索 id。

//Create your query as usual.. apply criteria.. do what ever you want.

//Get a unique set of ids from the result set.
var idList = query.
.Select(x => x.Id)
.List<long>().Distinct().ToList();

//Do your pagination here over those ids
List<long> pagedIds = idList.Skip(0).Take(10).ToList();

//Here what used to be non distinct resultset, now is..
List<T> resultquery.Where(() => 
item.Id.IsIn(pagedIds))
.List<Person>()
.ToList();

特别感谢.. https://julianjelfs.wordpress.com/2009/04/03/nhibernate-removing-duplicates-combined-with-paging/

于 2017-05-31T09:21:06.520 回答