2
有沒有什麼辦法可以改善這個查詢,我對返回的結果非常滿意,但是性能真的很差,這種情況下的union會導致往返嗎?通過使用存儲過程來獲得性能是否可以這樣做?是否有可能在結果上做自我加入之類的事情,並會提高性能?提高網站數據庫的搜索性能
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的文檔,到目前爲止,我發現它需要創建一個新字段,並在一個長字符串中創建所有字段。所以我不知道在哪一列找到了匹配,我說得對嗎?通過這種方式,我可以使用垃圾郵件關鍵字過濾優化過的網站。 – formatc
不要使用Linq2Lucene它是一個包裝,只需使用純Lucene.Net。您可以在單個「文檔」中定義具有不同內容的許多「字段」。 –