2
有没有什么办法可以改善这个查询,我对返回的结果非常满意,但是性能真的很差,这种情况下的union会导致往返吗?通过使用存储过程来获得性能是否可以这样做?是否有可能在结果上做自我加入之类的事情,并会提高性能?提高网站数据库的搜索性能
List<string> words = Util.Search.SplitByWhiteSpace(q);
using (WebsitesDataContext context = new WebsitesDataContext())
{
IQueryable<WebsitesRanked> query = Enumerable.Empty<WebsitesRanked>().AsQueryable();
query = query.Union(context.Websites.Where(x => x.Title.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));
query = query.Union(context.Websites.Where(x => x.Description.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));
query = query.Union(context.Websites.Where(x => x.Keywords.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));
query = query.Union(context.Websites.Where(x => x.Url.Contains(q)).Select(x => new WebsitesRanked { Webiste = x, Rank = 100 }));
foreach (var word in words)
{
string keyword = word;
query = query.Union(context.Websites.Where(x => x.Title.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
query = query.Union(context.Websites.Where(x => x.Description.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
query = query.Union(context.Websites.Where(x => x.Keywords.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
query = query.Union(context.Websites.Where(x => x.Url.Contains(word)).Select(x => new WebsitesRanked { Webiste = x, Rank = 20 }));
}
var results = query.GroupBy(x => x.Webiste).Select(x => new WebsitesRanked { Webiste = x.First().Webiste, Rank = x.Sum(s => s.Rank) }).OrderByDescending(x => x.Rank).Select(x => x.Webiste);
}
使用[Lucene.Net(HTTP://incubator.apache .org/lucene.net /)或Sql Server的[全文搜索](http:// m sdn.microsoft.com/en-us/library/ms142571.aspx) –
@ L.B我查看了Linq到Lucene的文档,到目前为止,我发现它需要创建一个新字段,并在一个长字符串中创建所有字段。所以我不知道在哪一列找到了匹配,我说得对吗?通过这种方式,我可以使用垃圾邮件关键字过滤优化过的网站。 – formatc
不要使用Linq2Lucene它是一个包装,只需使用纯Lucene.Net。您可以在单个“文档”中定义具有不同内容的许多“字段”。 –